When I set up a new Mac, there are a few things that make it immediately feel “off” to me. These are the small System Preferences tweaks I make that my muscle memory relies on.
Key repeat settings are in System Preferences > Keyboard > Keyboard > Key Repeat & Delay Until Repeat.
Focus all inputs is in System Preferences > Keyboard > Shortcuts > Accessibility > Use keyboard navigation to move focus between controls.
You can set this in System Preferences > Dock & Menu Bar > Automatically hide and show the Dock.