I am migrating Jenkins pipeline into gitlab

in exiting pipeline , we have many playbook and its role for configure docker,kubernetes, ecr, and many more.how we can migrate same ansible in gitlab.i knew we can move all file in gitlab easily.
i am new to gitlab and ansible.
how we can migrate it into gitlab

There isn’t enough info for anyone to give you useful information. At a high level, you’ll probably have to create Gitlab CI/CD pipelines. This doc may be useful Migrating from Jenkins | GitLab

You don’t mention if you have an AAP/AWX/whatever instance to centrally manage your job runs or give any detail on how you’re launching your job via Jenkins currently, so for all anyone knows you might just be running ansible playbooks via a shell on Jenkins currently. So if you’re using AAP/AWX you might need to hit the API, if you’re just running via a shell, I’m sure gitlab can do shell commands. Both would presumably require an on-prem Gitlab agent (if they have those, I assume it’s similar to Github, been a very long time since I touched Gitlab).