first time using a starter yeast.

I am doing my first 10 gallon all grain fat tire clone. I picked up a pound of amber breiss dry malt extract and a gallon jug. I have heard a yeast starer should be 2L. How long do i need to boil my water with the dry malt and how much dry malt should i use. Also do i keep the yeast in the fridge after adding my wyeast activator packet? Is there anyway to measur or figure out if the yeast starter is active. Thanks

2L sounds about right for a 10g batch of ale.
You will need 200g (7 oz) DME for a 2L starter
Boil for 15 - 20 minutes.
Keep the starter at room temperature for 24 - 48 hours to allow the yeast to multiply. The fridge is too cold.
Don't use an airlock. Most people use some sanitized foil over the top of the container. I use a sanitized jam jar. You need something that prevents dust and stuff dropping directly into the starter, but allows O2 from the air to mix with the air space in the starter.
Shake or swirl as often as possible (or put it on a stir plate to swirl it continuously).
You may or may not get krausen. I usually don't, but sometimes I do.
You can see that it is working by observing the yeast in the starter. (The amount of yeast should noticeably increase over 24 - 48 hours.)
You can also see that it is working when you swirl it. This will release some CO2 which you will be able to see.

-a.

It doesn't really make sense to say that a starter should be two liters, because starter size depends significantly on starting yeast population and beer gravity. If your fat tire clone is around 1.060 like most of them are, a 2L starter would actually be stretching your yeast extremely thin. According to the wyeast calculator, a propagator in 2L of starter will give you 4.47 million cells per mL when pitched into 10 gallons. For a beer of that gravity, you'd actually want about triple that. For ten gallon batches of an even moderately big beer, it is mighty mighty hard to get a good single step starter from a propagator. Consider doing a few steps, or getting an activator (or two) next time.

+1. 10 gallons of 1.060 wort will need roughly 12 million cells / mL. You won't get that from a 2L starter.

10 gallon batches are really difficult to pitch correctly from a smack pack/vial and just 1 starter step. It may work for a low gravity, sub-1.040 ale but that's about it.

For a batch this size at 1.049 og, I just went from vial to 1L starter to 5L starter. Let settle and then decant & pitch. I started a week ahead of time.