Hi t.walker.12,

I don't think this is a big deal. Plenty of guitarists learn the instrument while sitting down, with knees crossed, etc.

The more important thing is to determine whether your shoulders, back, wrists, and hands are comfortable. Those are the main parts that can get strained while holding/playing guitar.

Alos, just make sure, when you're learning, that you don't crane your neck over the guitar, play in a relaxed position.