How to recover the source code from gitlab objects

Hi,

I am so confused and don’t know what to do.

I configured my Gitlab locally on ubuntu 18.02 and upload my projects there.
Now, I got a problem in my ubuntu O.S, so I needed to fresh install Ubuntu.
In this case, I make a copy of the /var/opt/gitlab/ dir and install a fresh version of ubuntu.

The main issue here is that how can i restore the repository back to my Gitlab?
I search for .pack extension files and check that all the files are in compressed form.

I search for help on how to get back the source files from here but no way…

Please help me in this regard.