I bundle things together. And try to waste as little time as possible. Very little social media, and zero Netflix or YT rabbit holes.

IE: while kids are in the playground, I do calisthenics and yoga.

I got with my son bouldering together, so both of us get a workout and share time together.

As soon as I have a small gap of time (IE: kids go to the bath tub together), I read and study in one of the languages I am learning.