When I create a new file in a git tracked folder and click commit it doesn't show for commit. If I want to show it, I need to right click, then click Add ... then to commit it. Other users can commit without the Add step. I am master of the project in GitLab.
Other problem is when I want to push every time TortoiseGit requires me to re-enter username and password, but when someone else (my friend) try to do that, it doesn't request his.
Make sure the Show Unversioned Files is checked. See:
For your second problem, go Settings/Git/Credential and try to use manager helper. Also see A: TortoiseGit save user authentication / credentials
Make sure you don't have a rule in your .gitignore file that might be excluding files unexpectedly. For example here I have localhost.pfx set to be ignored but the right-click context menu still allows me to add it to a commit: 
On similar issue:
I wanted the Windows Explorer to show git folder as changed (red color) when a new file is added.
Below worked:
> Tortoise > Settings > Icon Overlays > check the box "Unversioned files mark parent folder as modified" > Apply & OK > Restart computer (since it is explorer extension it is not working without restart) Hope that helps.
Under the settings for TortoiseGit, there is an option on the Dialog 2 tab for Select Items Automatically
To remember your password, you'll need to save your credentials. See the credentials tab of the settings. Depending on which one you have installed, you can select the appropriate credential helper.
See the TortoiseGit Settings doc for details.
On a side note, having to manually add your files for commit is usually not a bad thing, there are many scenarios where it is advantageous to thoughtfully craft a commit over just adding all the changes in your working directory brute force.
untrackedpath/file.txt to my filesystem, git will only show me untrackedpath/ as untracked in the status.You can remove your .gitignore file to have a clean start or edit it if you see what is wrong with it. In my case, I don't know why, I had a *, so everything was being ignored, I just removed it and everything worked fine again.
