Cossy
I agree, I learned far more after my school and college years than I ever did actually at school/college.
Read, research, use the internet, newspapers etc.
Identify how your learn best (ie your preferred learning “style”) and those things you want to learn about and are interest in.
I’m still pretty rubbish at world geography and sciences. But, I have far more desire to learn about those things now and I enjoy looking at atlases and maps online and reading up on science based subjects.
You could enrol online on any number of free online learning resources or classes or look at adult education classes in your area.
Good luck and you’ll find your own way of retaining facts.
In some subjects at school, I think I learnt a framework on which hung subsequent facts I heard. My science framework is poor so stuff like Attenborough programmes or documentaries about space exploration goes in one ear and out the other.
In answer to keronbwan, Sporcle is useful. I do remember learning PMs of UK a while back entirely from one Sporcle quuz
