Kids will generally have fun with anything you show a degree of interest in. The copper pipe plumbing example in this thread is a perfect example. A simple Task became a life long activity for the kid. They will remember it forever and tell someone in the future “this time I welded with my dad”… they won’t remember that time my dad didn’t hire a plumber.
Things off the top of my head that have been a hit - Planting plants Fashion design Basic coding activities or contests Shooting Anything that requires safety procedures Lawn work (but make it fun or set a timer) Writing a story where they write some of it, you add in silly bits, they write more , repeat till laughing out loud. Both my girls super in to etiquette
Best of luck buddy and squeeze these years for as much as you can.