What are some good Linux training centers in Moscow?

Question

linux

I plan to study in Moscow in the training center between October and mid-November, where courses on Linux would be taught.
I work with CentOS, at the Specialist, unfortunately, they teach courses on Ubuntu and FreeBSD, I would not want to interfere with Ubuntu with CentOS. The purpose of training is to systematize existing knowledge from the basics and raise it to an advanced level.
Could you share your opinion, recommendation (preferably based on personal experience) which training center to choose.
I came across Inventa, can you say something about this organization?
You will have to pay a lot of money for flights / accommodation / study, so I would like to get the maximum.

Answer 1

I would also learn on Linux, you can without certificates, without everything

Answer 2

Not quite sure, do you want to learn Linux, or CentOS?
If it's the former, then enjoy the Debian/Ubuntu courses!