no, you have to generate a PAT (Creating a personal access token - GitHub Docs), its sort of like a password then on the wiki you have to click the cog and find the github settings and paste it in there along with the github account name and other stuff, that field is then saved locally (I think as a cookie but not sure) so you have to do it the first time you time you try and make a change from that device/browser. (IF you don’t have the PAT in, it will “download” a copy to your downloads folder)
One thing you can do to limit the risk of the PAT is to create a new github account that has just your tiddlywiki’s as this reduces the reach of the PAT and treat it like a password.
A PAT will be about this length and contain “random” characters, letters, numbers etc, MIGeMA0GCSqGSIb3DQEBAQUAA4GMADCBiA (please note this is not actually a PAT)
It all depends where you want to access it from. From a personal security POV, I would not recommend making an IP and port in your home reachable from anywhere unless you really know exactly what you are doing and the security risks that are involved in doing that.