Resources/sites for online courses

[RaamGeneral]

Hello. I'm looking for a list of resources or sites that offer online courses especially at university level, of course also paid. The subjects I'm interested in are, among others, physics, mathematics, chemistry, computer science, biology, ... Let's say I want to make good use of my free time: I've still got an appetite for learning even though for some years I'm having some problems with concentration. I couldn't continue university and I have big trouble studying books.

So I know it's a bit contradictory. It's not like I expect to master the topics and being able to solve most problems.

 

[hutchphd]

A bit of unsolicited advice:
Why don't you think smaller. Find one thing that you really want to understand and work outward from there using all the WEB resources available. Knowing a little bit about something puts you well ahead of the curve. Knowing nothing about everything does not.
Personally I am a fan of MIT Open Courseware and YouTube (carefully applied)

 

[Baluncore]

I'm having some problems with concentration. I couldn't continue university and I have big trouble studying books.

Perhaps you need the excitement of exploration to maintain your concentration, a bit like the sufferers of ADHD.