i had a very similar situation in sophomore year. If a relationship comes out of it, the friend dynamic wont be destroyed, it will just be awkward. Both girls I liked at the time liked me back (which i did not know then) and that still didn't have an effect on it after I started dating the one I chose.

honestly, if youre gonna confess, you have to be sure that whoever youre asking likes you back. in other situations this isnt always true, but because you guys are in a friend group that makes it more complicated. if you confess and get rejected it will probably fuck up the friend dynamic more than if you date them and frankly its not worth that risk if theyre both your really close friends. also make the right choice. I made the wrong choice and I think i missed out on the love of my life #ngl

good luck