Learning to draw with your left hand would be a handy (pun not intended) but ultimately useless and needlessly difficult thing to focus on, especially if you're not already ambidextrous. If you're worried about your right hand deteriorating over the years, I'd suggest just practicing joint stretches, like the ones listed
here- but as long as you know when to take breaks from your work (i.e. if you hand starts to hurt from strain, taking an hour or so to rest it) I doubt you'd have any problems with your hand until you're a few decades older or at all.
If you still want to learn how to draw with your left hand, go ahead! I'd be a neat trick to show to your friends at the least, even if it would be difficult to get used to.
