Yeast confusion (first time fermenter)

I have started to "try" and make a hard cider, but I don't understand all of what I'm reading about yeast. Lots of the stuff I read talks about pitching the yeast to jumpstart it for use when preservatives that inhibit yeast (potassium sorbate) are present but I also see it mentioned in articles when you press your own apples which would have no preservitives. I picked up some organic apple juice from Whole Foods that has no preservatives and I'm not sure where to go from here. I would really appreciate some help understanding that. I'd love to be able to just throw some of the yeast into the jug and have it work (nice and easy).

The other question I have is about how much yeast to use, though that I figured I could probably end up figuring that out through trial and error. If anyone can help clarify how much yeast I should be using that would be great.

I added 0.5 cups of brown sugar to the apple juice so the yeast has extra sugar to ferment.

It depends on the gallon / batch size you are brewing. I am still in my first year of brewing and by no means an expert but I started with ciders because 1) I like them and 2) they are simpler than beers for the most part.

You still need to add a bit of brown sugar to the juice, if you want to get the gravity up. Brown sugar is a good choice. I used 2lbs of brown sugar for a 5 gallon batch.

As for yeast, if you rehydrate the dry champagne or monotrachet yeast for about an hour, you can just pitch it right into the juice and see fermentation start within 24-36 hours.

I am starting with 1g jugs of juice, so my 0.5c of brown sugar is slightly higher than your 0.4c per gallon.

I picked up 2 kinds of yeast (not knowing what I am doing I figure experimentation is not all bad if I get some of the basics right). I have a 11.5g saflager packet and 1lb of Distillers Yeast (DADY). I assume when you say rehydrate you mean to put the yeast into a cup with some water, and I'm guessing room temp since yeast doesn't like cold. After the hour do I strain it or pour the whole mix into the jug? If I just throw the yeast into the jug, will it hydrate in there since apple juice is largely water?

Thanks for your quick response. And your less than 1 year of brewing is still a lot more than my brewing time of zero.