I feel stupid for not knowing! But I need advise on sex positions...

Somehow being on top is ridiculously awkward and uncomfortable for me. I can't seem to get enough leverage with only my knees on either side of my SO's hips. I can squat with my feet on either side, but then thrusting feels very... awkward...

And how on earth do people have sex from behind? (like doggy or whatever people call it) for me, those positions just don't seem to work! If me and my husband even manage to get it in from that angle, it slips out pretty forcefully almost immediately when we start to thrust. We somehow managed (uncomfortably) once, and afterwards,I realised I was bleeding pretty significantly... so we didn't try that again!

Otherwise I'm suck with missionary, with don't get me wrong, it's great, but I'm pretty sure having other options would be preferable.