Do online courses/certificates actually mean something to companies/universities?

Coursera courses? OpenClassrooms? Stuff like that.

Probably not as they compete in the same space.
Do you mean as entrance criteria?
Have you already done those courses and finding employers not interested or are you interested in doing further study?

I would say it's probably a nice extra, if you've already have an education. Those online degrees are no replacement for an initial apprenticeship or college.
But depending on where you live if you can build impressive stuff with said knowledge you may get hired without a degree.

Nope

here is another good question... do collage degrees mean anything ?

I know they don't where I work.

also my brother in another company is involved in the hiring process and they couldn't care less about collage degrees while they care a bit about online courses...

it depends on the employer or the team (or the guy) who is responsible for hiring...

They mean very little to me as an employer. Showing what you did (actual code, and demonstrable real life experience) mean much more.