im not sure if you still need advice or not on this considering this was so long ago.. but if your looking for new style options you don't have to spend a lot, like urban behavior, American eagle, heritage 1981..even ordering stuff off the internet can be cheaper.. depending on if your parents will let you use there credit card. but anyways if you think your super skinny try T sh*ts that are fitted but not tight, and layering could work really well for you.. like wearing jackets over a button up shirt that has a t-shirt under it. or even just wearing cardigans over t shirts, I'm not exactly sure of your style but it might be fun to try something new. for your description I would say the more button front shirts the better. there sophisticated and casual and can go along way when it comes coming up with many different outfits. also just some trendy T-shirts or hoodies would work really good to. like these for example..
link as for jeans, I'm not sure if boot cut really works for anyone, and you don't have to go uber skinny. any straight leg jean or a jean with a bit of skinny cut would work really well. but don't go tight just go a tiny bit baggy something like these..
link hopefully I helped!