Environnement web and my gitlab rippo

Hi community

I’m looking for doing something very simple but cannot find the way how to.

I have rippo on my gitlab for each applications on dev in my company.

I have debian serveurs with Apache service.

I’m looking to link my rippos to a web environment so the developeprs can push and merge and see their modifications straight to the environnement https://app1.domain.com

Thank you for help