ruby on rails - Adding Fetch button on the project Menu -

I am new to GitLab (and also Ruby on Rail).
I am trying to add a new feature:

Br> me the project menu (where ssh / http link and Downloads / tags are displayed) on the "add code " button. Its purpose is as follows:

1. If the @ project.import_url is set, first check it.
2. If the set is received by the parent repository and if any new branch is available, add it to merge the request.

   I have tried to do this using simple online tutorials and / app / views / layout / nav / _project.html.haml file, references and Also adding the required file to the config folder. But this does not seem to work.

   If you can tell me several steps, then it will really be helpful.

   The closest example of this is to look for a commission like this:

   " ".

   As you can see, more than one .html file is affected.
This is not a project menu, but still can give you a starting point.
You should get more information.