how to make a selenium project run on a build of another project before it's deployed using gitlab CI ?

So this is a question of concept more than technical, Say I have two projects project A is the project that I’m testing, it’s a website that is built with angular 8, and project B is the selenium testing framework that has all my testing scripts that will run on project A,
NOW both projects are on GitLab in separate repositories.
Question 1: on a merge, for project A with new code, a build will happen with the new code if successful then I want to trigger the build of project B and run the tests on project A’s new build

( is it possible ?)

Question 2: if it is possible how do I access the build of project A when I have already defined the URLs that selenium will run the scripts on?
thank you in advance for whoever is willing to help and I’m sorry if this question is considered a dumb question

@Amineslaimia - Thanks for posting! I think that multi-project pipelines should enable you to do what you’re looking for.

-James H, GitLab Product Manager, Verify:Testing