Do you go to a gym? Are there any trainers there? They’d be the best people to speak to. Ask if they have any kinesiologists. Sometimes gyms provide free training sessions and you can get great advice.
Otherwise you can look on YouTube for exercises. Athlean X is a pretty good reference. But there are a lot of physiotherapy channels as well that have good information.
You should get the Pantheon desktop environment for a more Mac like experience.