I don't know that it would burn, but I tie the drawstring cord around the pot handle to never let it touch the bottom.
So you've been bitten by the brewing bug, hopefully. It's a really rewarding hobby. For me it started out a hobby which lead me to go pro.
Don't know why you would burn the bag, when using any grain, you do not want to boil the grains at all! Simply steep them in 150-160 F water, usually 15-20 minutes is sufficient, you're not converting anything. After the steep, remove the bag, don't squeeze! This will add off flavors and tannins.
You can now bring this tea to a boil. I usually boil before adding the extract, if I am doing an extract brew. This can help it from sticking to the bottom and it dissolves a lot faster, especially when using a liquid extract. If using dry malt extract, expect clumps and sticky hands, and watch for boil overs. I find that DME (Dry Malt Extract) boils over more than using LME (Liquid Malt Extract). Stir is until it is dissolved. Some people boil until they see a protein break, you'll see a foam when it first starts boiling, when the foam finally dissipates, you have just completed your break. Now you can add your hops and whatnot. A few things to remember, don't cover! This will create cooked vegetable flavors in your beer.
Use Irish moss, this is a kettle coagulant, you add this about 15 minutes to the end of the boil.
If you are worried about haze in your final product, simply dissolve some gelatin in water and add to your primary, then rack to your secondary. Finings like gelatin will reduce the amount of time it needs to spend in secondary and you will end up with a clearer beer.
Good styles to start out with: Stouts, Pale Ales, and IPAs, why? You can mask a lot of mistakes with darker malts and hops.
Chilling, some people use an ice bath, just be sure to keep it covered in the ice bath so you don't get and wild yeasts. Lactobacillus can take over quickly if you leave the lid off for too long, this will make your beer sour, which is great if you're trying to make a sour. Chill as fast as possible. At around 160-170 F there are a lot of bacteria that can and will infect your beer. You want to chill to about 65-70F if doing an ale, too high you might kill the yeast or end up with gallons of acetone.
Other methods of chilling. Invest in an immersion chiller. You can usually chill your wort down to target temp in 15 minutes or so, but you are still risking infection if exposed to open air.
Better still, plate chillers. These are closed, no exposure to air, they can be hell to clean because they get clogged. You can usually back flush these pretty easily. To avoid clogging, right before transferring, if you have a valve on your kettle, drain off some of the wort till you see no more sludge. This is called cast off. A plate chiller should cool your wort down pretty quickly, but be sure to regulate the flow or it won't cool all the way, this is especially important if you are doing over 5 gallons at a time. You can top off will cold water, but again, you risk contamination.
Avoid splashing it around too much, a little oxygen is okay, it helps the yeast along, but too much and you will end up oxidizing your beer and it will have off flavors.
Once your wort is safely transferred and chilled, add your yeast. You can start off with a starter, mix some cooled wort with the yeast, some people do this the day before and keep it refrigerated until brew day, if you don't go this route, if using liquid yeast, shake it up in the vile or if using a smack pack, smack it at least an hour prior to pitching. Dry yeast, you can usually just pitch it as is, fermentation make take a little longer to start, but it will start.
Avoid lifting the lid to check out how fermentation is coming along if using a bucket. I'm not a huge fan of carboys because they can easily be exposed to light, which will skunk your beer. So be sure to keep it in a cooler, darker place.
On transfer day, like I said above, if you are worried about clarity, add some dissolved gelatin before transferring. I do this so there is a more even mix. Again, avoid sunlight, extreme temperatures, and checking under the lid.
On bottling day, if you are going that route, you can clean your bottles in the dishwasher, but to be extra safe, put them in a solution of iodifur or star san, but only do this after the are cool. These are no-rinse sanitizers. With iodifur, be sure to not use too much or you will get this almost medicinal flavor. Bottling trees are extremely useful for letting that excess liquid to drip out, just be sure to sanitize the bottling tree.
Priming, boil the corn sugar that might come with the recipe kit. You'll want to boil this for about 15 minutes to sanitize it. Avoid using table sugar, this will give your beer a cidery flavor. An alternative to corn sugar is to dissolve malt extract. Add this to your bottling bucket, some people let the priming liquid cool before adding, but it really isn't that necessary, it will cool when the beer hits it. Adding the priming liquid first and then racking your beer into it, will help to provide a more even mix. Don't bother stirring or shaking it, this can lead to oxidation and/or infection. Another alternative is to use priming drops, it's basically a sugar pill which you drop into each bottle. Just make sure your hands are clean. Now bottle! The spring loaded wands are a good way to go, make sure it presses down on the bottom of the bottle, let it over flow just a bit, you are more likely to get a more even fill and this will help to get excess air out, which could lead to beer spoilage and oxidation. Make sure your caps are sanitized, again, you can use a few different no rinse sanitizers, I usually use a bowl of solution to soak my caps, contact time should be anywhere from a few minutes to about 15 minutes. Spray bottles of the same sanitizers work in a pinch too, but I'll cover that later. If bottling solo, once the bottle is filled, place the cap on immediately, you don't have to crimp it just yet. Just letting it sit there with the cap on loose, can let excess air escape, which is a good thing. When you have your bottles lined up and filled, use the capper. Store in a room temperature room, with little to no light. Alternatively, after you've waited about a week after bottling, let it age a little in the fridge. Avoid over priming and excess temperature fluctuations, or your bottles will explode. You can use a little less recommended priming sugar and it will carbonate, it will just take a little longer.
Sanitizing: Can't stress this enough. Sanitize everything! Also, I highly recommend getting a spray bottle and either fill is with sanitizer or isopropyl alcohol. Before connecting any hoses, be sure to spray the ends of the hoses and any valves.
Hope this helps.