Variety science YT:   SciShow       Real Science▸Shorts       Today I Learned Science▸Shorts       Gabriel Torch▸Shorts       AsapSCIENCE▸Shorts       Kyle Hill▸Shorts       Veritasium       Be Smart       Vsauce▸Shorts           Sabine Hossenfelder▸Shorts       Cleo Abram▸Shorts       Anton Petrov▸Shorts

Maths:    r/askmath    YT:    DIBEOS       3Blue1Brown▸Shorts       Beau Janzen       Dr. Trefor Bazett                         

Physics:    Wikipedia :  Classical mechanics    Physical cosmology    Quantum mechanics    General relativity  YT:  Arvin Ash       Sixty Symbols       vt.physics▸Shorts       Tibees       ALL OF PHYSICS explained in 14 Minutes (video)

Practical science YT:   The Action Lab▸Shorts       Steve Mould▸Shorts       AlphaPhoenix       The Thought Emporium
Chemistry YT:  NileRed▸ Shorts       NileBlue▸Shorts       Cody'sLab       Explosions&Fire       Chemiolis       GENERAL CHEMISTRY explained in 19 Minutes (video)

Learning portals:    OpenLearn       Khan Academy