Ring finger fretting hand (left hand)

I can't get good control over my ring finger of my fretting hand. The distal joint of that finger (D. I. P.) wo t bend much even using my other hand to bend it. Also when moving the ring finger from the Cchord to the A minor chord the ring finger catches for a second and then seems to pop into place. What's going on? Anybody know how to solve this? I'm a relative beginner. Just getting into the power chord section of Lisa's lessons. BTW, I'm 72 yr old.

Thanks for writing in! Your ring finger is the weakest of the guitar fingers. No worries if you don't have total control over it. That ring finger might be the last to behave. Just keep at it!