Permission denied whil SSH connecting

I have a problem with connecting to gitlab via SSH.

Before that I have create a pair of keys like described here:
Saved the public key in settings of my account on
Saved the private key on my server (under CentOS 8).
And finally I type

ssh -i /home/admin/.ssh/gdever -t

Any Ideas how to solve it?

@gdever SSH connection is a way to for you to connect to Gitlab repository so that you can synchronize changes between a Git repository and the other from Gitlab.

To test SSH connection to Gitlab, run below command
ssh -T