Use the GitHub integration
Before you begin, ensure that any GitHub users who you want to map to GitLab users have either:

A GitLab account that has logged in using the GitHub icon - or -
A GitLab account with an email address that matches the publicly visible email address in the profile of the GitHub user
User-matching attempts occur in that order, and if a user is not identified either way, the activity is associated with the user account that is performing the import.

If you are using a self-managed GitLab instance or if you are importing from GitHub Enterprise, this process requires that you have configured GitHub integration.
1.From the top navigation bar, click + and select New project.
2.Select the Import project tab and then select GitHub.
3.Select the first button to List your GitHub repositories. You are redirected to a page on GitHub to authorize the GitLab application.
4.Click Authorize GitlabHQ. You are redirected back to the GitLab Import page and all of your GitHub repositories are listed.
5.Continue on to selecting which repositories to import.