You don't mention what your health issues are. That's first and foremost. Nor do you specifically mention what your goal is...outside of cycling in general.
So depending on your health issue(s), that would be the starting point for what your goal is.
If you can't get on your bike now, I'm not sure what good an ebike will do you. Unless you get a step through. And e-bikes in general, well IMO I personally would question the effectiveness of the health benefits, comparatively speaking to normal cycling. But honestly, it's certainly better than sitting on the couch.
Cycling is one of the most low-impact yet high intensity/benefit exercises there is. Low impact as far as impacting body/joints/muscles.

A 61 year old heart isn't that old. Mine's about to turn 65 and I'm riding 40-50 mile rides regularly and really what's driving me off the bike is sore butt issues...which I'm working on. But again, you don't mention if you have a specific heart issue. Regardless, you can call yourself old if you want to but you can choose to act old or not. We are not our parents or grandparents generation. It's up to you.

I'd talk to my primary care doc and ask him to give me some guidance on how to work back towards regular cycling. If he tells you to avoid it, find another doctor.
And just another thought, Pelotons are fairly frequent on Marketplace now, and seems the asking price around $500. Maybe something to look into.

Anyway, all the thoughts or advice in the world won't make it happen, only you can do that. Good luck.