You do have keyboard shortcuts in Free, the problem is that you can’t customise them, so you’re stuck with them. They may also clash with your browser’s shortcuts. You should have the standard ones like this:
https://help.sketchup.com/en/article/3000081#qrc
There’s others not on that list, like these:
⌃⌘ drag left mouse button - Orbit without changing tool
⇧⌃⌘ drag left mouse button - Pan without changing tool
You can slow the mouse scrolling a bit in System Preferences/Accessibility/Mouse&Trackpad/Mouse Options
I used to use MagigPrefs from http://MagicPrefs.com but it is no longer supported. It let you change mouse settings for certain apps automatically. I really don’t need it anymore.