Explore Stream

The epicentre: https://www.raspberrypi.org/

Good linear learning through practical work: https://gpiozero.readthedocs.io/en/latest/

Another fantastic resource from Google is Flow (Formerly Google Garage) https://grow.google/intl/uk/courses-and-tools/

A fantastic free resource to learn rare and VALUABLE skills: https://applieddigitalskills.withgoogle.com/s/en-uk/home

If your connected education is available. It's focus that is often in short supply: https://www.edx.org/

It's just a share fest, but here's my first recommendation. https://www.p2pu.org/en/
I love open source nearly as mush as I love peer to peer learning as a practice. Give a man a fish and you fed him for a day, but if you teach a man to fish you feed him for life. (anon)