If it's chrome under the paint, then something like CitriStrip will take it off with no problems. I used CitriStrip on an old Nishiki that had a chrome fork and non-chrome frame. Some parts of the frame required a bit of sanding to remove. A lot of it wrinkled and scraped off. The paint on the fork wrinkled and wiped off with very little effort exposing nicely protected chrome underneath. I painted that bike with a spray can, and the results were decent, but I've had already had a spot of two where the paint chipped on the fork.
If you're planning to paint the bike yourself with a rattle can, then I think your best course of action depends on how well the current paint adheres to the chrome. I'd probably start with some scuff sanding, as you've considered. If the paint doesn't come off in flakes when you do that, then it probably has better adhesion than you'd get with rattle can primer. In that case, definitely paint over the existing paint. If it does flake off when you sand it, then you'll need to do something more. Possibly taking it down to bare chrome and then roughing up the parts you want to paint over, followed by a very good etching primer, then a sandable primer to smooth out the surface, then paint.
I think @
randyjawa has some experience painting a chrome frame. He'll recommend hand painting, and based on his results I can't argue with him.
It's a lot of work to get this right though. Immense measures of patience and sanding. If it were me and the paint flaked off when sanded, I'd send it off to be powder coated.