Hi,
Is it mandatory to use CodePen for the projects or can I build my tribute page on my own domain?
Thanks
No it is not mandatory i quote " * You can build your project by forking this CodePen pen. Or you can use this CDN link to run the tests in any environment you like: https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js "
As long as they can see your project through the link and there is the testing script in it . I don’t see a reason why they wouldn’t let you do it 
Great thanks - wasn’t sure what it quite meant by forking but now it makes sense. Learning Git at the same time 
Forking just means to create your own copy by whatever means. Since the original and your copy then go off on different paths as they’re developed, it’s called a “fork”, like a fork in the road. It’s a way older term than git or even most version control systems