Linux: Allow one user to manage all files from another user/group
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I just installed `lamp-server^` on my home linux machine. 
Now I created a new folder `project` with files in the `/var/www/` directory (server root directory). I set the owner user/group to `www-data` via `sudo`.

Now I want to access the folder and its files via `cd` or normally via the file explorer, but I get the error that I haven't the permission to do/access that folder or its files (with my normal user account). 

Is it possible to give my user account the rights to access/modify the `project` folder?