Should you ask out a girl who i fancys but dont know if she fancys me?

If you have feelings for her, it's worth taking the chance to ask her out, as it can provide clarity about her feelings. The worst that can happen is she doesn't share your interest, but you'll gain confidence and know where you stand. Try to approach her in a relaxed and friendly manner, which can help ease any potential awkwardness. Trust your instincts, and go for it!