Connection to a private repository

I’m an SAP Admin & our Devs are looking to start using Gitlab, I have zero knowledge in this area so looking for some guidance really. There doesn’t appear to be too much on the SAP side !
So here goes…
Has anyone on the forum been succesfull in connecting to a private repository on Gitlab and how did they do it ?

Currently we see a redirect & that’s as far as we get.