Bestt way to get to know Sorento Italy?

Sorrento is very walkable, basically flat and compact, mostly pedestrianized
Your feet should work just fine

Or do you mean visiting the Amalfi Coast from Sorrento? (which is not on the AC)

Your previous post
https://community.ricksteves.com/travel-forum/italy/off-the-beaten-path-sorrento

Sorrento isn't a place tourists typically go to sitesee. It's a base to stay to visit other places such as Capri, Amalfi Coast and Pompeii. Where are you coming from and what are you hoping to see? With those answers we can help point you in the right direction.

The tourist center of Sorrento is not all that big and easily walked. I can't imagine you'd get any benefit at all from a driver or bus. Here's a self-walking tour from the city's official tourism website:

https://www.sorrentoinsider.com/en/e/sorrento-tour-walking-itinerary

Ignore the link on that website for a hoho bus: there isn't one of those in Sorrento anymore.

There's also this:
https://www.mywanderingvoyage.com/blog/a-slow-travel-walking-tour-of-sorrento-italy

We just returned from a trip that began with four nights in Sorrento......I agree that you do not need a tour. Just walk around alone.....Piazza Tasso, maybe down to the two Marinas, the liitle lanes filled with shops just off Piazza Tasso...art galleries...it's very pleasant....go for a dinner in Sant Agata, in the hills above Sorrento, where you will have views of the two Gulfs.....Gulf of Naples and Gulf of Salerno... Some great restaurants up there....

If you can find a hotel with a terrace and view of the Bay of Naples and Vesuvius, even better!!