Is there such a product as a manual can opener that is EZ to use and SMOOTH to operate (painful hands is the issue)? Thank you?

They're out there.  EZ-Duz-It and Swingaway are pretty much carbon copies of each other, providing plenty of leverage for both closing and cranking.  When my wife's arthritis started becoming an issue, we got a new Swingaway and it's...better.

If you have painful hands you may just have to bite the bullet and dedicate an outlet to an electric.  That's the lowest-effort option you'll find, unless you can find one of the old-fashioned, wall-mounted kind with the BIG crank.

I have one of these:

https://www.hartsofstur.com/swing-a-way-wall-mount...

I find the crank action very smooth and easy.  Whether I would recommend it or not depends on if you can hold the can one nanded while loosening it after opening it.  That's the only issue.  I can't manage traditional can openers at all.  Sometimes my left hand can be a little unexpectedly weak and I worry that I might drop a can, but so far so good.

Might depend on why your hands are painful, or what part of them is painful, and how painful. I have a Swing-away one that's easy to operate. I clean it and oil it very lightly from time to time with Tri-Flow oil, and that helps keep it going smoothly. I have another, the Chef'n EZ Squeeze, which you operate by squeezing the handles, like a pair of scissors rather than by twisting a handle. For some people, that might be easier. It's a little trickier to get placed right on the can but once you do that it works nicely.

My favorite one is from Pampered Chef. OXO also makes good ones that are available in the store.

Get an electric one that restaurant kitchens use.  Not cheap.

Never found one , I have arthritis, you need an electric one.