Ellen, you 'll do fine - I'm up there in age too compared to some of these young 'uns - maybe a little less strength, little slower bouncing back (as I've been noticing in many areas since passing age 60) but you'll do fine.
Arm strength helps getting out of bed and chairs but they'll teach you how to do it. The leg will feel a heavy and sluggish at first and I certainly needed help lifting it to get in bed - then figured out I could grab my pant leg about at the knee and help it lift. My bed at home is quite high so I put a small stool by it at first, sat down, scooted over as much as I could with leg out straight and rotated the legs onto the bed. I was surprised when after a few days I could just lift that leg. My doc did not prescribe PT (except what they do in the hospital) and I've gotten along fine at my own pace. Don't push too much!