is it possible to save more than one thing to the clipboard

I very much like the BetterTouchTool clipboard manager. You do have to bind a trackpad, mouse, and/or keyboard action to invoke the BTT Clipboard manager, but after that I find it fantastic.

And I get all the other BetterTouchTool features to customize the trackpad, the mouse, the keyboard, and the touch bar.

https://folivora.ai/

No. There are third-party clipboard managers that will however.

You're welcome. As far as I can tell, Paste is the most popular. It's in the App Store.