How long is the oven supposed to be preheated? and at what temperature?
the temperature for the oven is part of the recipe/on the back of the cake box. most ovens have lights that turn on when the oven is turned on. when the light goes off, the oven is pre-heated. otherwise, leave it for about 15 minutes and you should be good.
I made a cake over the weekend using boxed batter. I only wanted to make one layer though so I halved all the ingredients. The sides were tough but whenever I inserted the toothpick, the end would come out wet (which meant the bottom wasn’t done yet). But it was already going way past the recommended baking time and the ends were burning. Wat should I have done differently?
i don’t ever halve the ingredients of a cake. rather, make the full cake, but use one pan instead of two, and voila, you will have a one-layer cake. halving things like eggs is always tricky.
What would you recommend for an absolute beginner?
The stove top/burner serves the same purpose as a cooling rack, right?
no, a cooling rack looks like this- http://www.kitchenfantasy.com/images/cooling_racks_single.jpg
you can get it for pretty cheap pretty much in any store that sells kitchen supplies.
What about the sides of the cake? or it wont stick to it, right? 
**you don’t apply wax paper to the sides, you lightly butter the sides. when a cake is done, it tends to shrink, i.e. pull away from the sides of the pan. this is another indication its time to do the toothpick check, btw- when you see the cake has pulled away from the sides of the pan.
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Okay my question for all of you…did you ever start baking by using the boxes (betty crocker, duncan hines etc) or did you start baking totally from scratch?? Any time i go to the store..i get sooo confused and overwhelmed by all the variety there.
**i started with box mixes. they’re super easy and after mastering those, you can start on the cakes from scratch. **
I know practice is everything…but how do you practice the decorating part (with the tubes and gels) but not waste so much product? Do you use the tubes as they come from the store or do you add attachments to it to make em easier to use?
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i wouldn’t waste your time with tubes and gels. the icing in them tastes way too sugary and they rarely work. when you are ready to experiment with icing, then we’ll talk about piping bags and tips 
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This is a whole new arena for me so I have a zillion and one Qs along the way