How do I play two strings with one finger on different frets?

Question

I have to play one fret that's one over from the other and one above it on the next one when I put my finger sideways to play it I always get the lower one instead of the one next to it

Answer 1

This is on a guitar right?  You're going to use another finger for one of the frets, or tilt your hand in an uncomfortable form.