Our team is not familiar with Git and I feel like we are not using it correctly.
They have opened a github account with the lab’s name. different people (not necessarily working on the same project) have a folder with their name and they use that to organize their code. If one needs someone else’s code, he copies it to his own folder and uses it as he wants.
This is a small team of about 6 people (working on different stuff sometimes) so the codes are not changing very fast.
Is it the correct way of doing this? Or should different people have their own account and fork the project and merge it later?
Is there any good tutorial out there?
Each of your team members should have their own GitHub account, not one for the whole team. You may want to consider creating an Organization or turning the current account that owns the repository into an Organization at https://github.com/settings/organizations (free for open source). Add each team member as a collaborator.
From there, team members can work in branches, their own personal forks of the repository, or all together in the master branch of the main repository.
In any case, they should not be copying code back and forth in personal folders in the repository. That largely defeats the purpose of having version control in the first place. If I need to use your code and copy it to my folder, and then you make changes to your copy, I am now working with out-of-date code.