Yes, there is two ways you can go about this. The way that you are thinking of (and the way that I would ideally like to go about this) is as listed on this help article. This is perfect for sharing a home server to some friends, and letting them access a given service without seeing any of your personal devices.

The other option is to have just one tailnet, but having multiple users as detailed here. Notably this can be a security regression (if you don’t limit access on a per-user basis with ACLs), but is ideal for sharing access to your entire network with your spouse / older children within the context of self-hosting.

For example, I have a friend who has shared a minecraft server with me and that is an ideal example of sharing one node to a seperate tailnet. I am an admin of the server, and can manage the docker container for it + the backup sidecar and the SMB share, but that is where my access to his network structure ends.

This contrasts the situation with my partner for example, where we share a tailnet (with seperate user logins) to make things like gamestreaming just that much easier to setup. Hypothetically I can use ACLs to limit access to stuff like the Cockpit web-management portal, or block the SSH port, but I don’t feel like I need to in my specific case.

Addendum: I also think sharing the device out strips it of its subnet routes + services, which is part of the problem I am running into where I do want it to strip subnet routing (my elderly parents DO NOT need access to my printer), but I ideally want to be able to still use tailscale serve + services + https certificates to be able to share my self-hosted RSS feed reader for them (ad-free, no AI slop, much better for my one parental figure with early-onset dementia).

Addendum 2: I highly recommend exploring tagging + ACLs if you are looking into personal usage / seperation of networks. It is just a much easier approach of seperating devices that are owned and operated by the same person. I would only explore multi-tailnet option when it is different users and you want to share a very limited scope of your network.

I still think a syncthing client of some form is ideal. As someone else mentioned there is the option of using the Syncthing Tray devs experimental android build. To avoid issues with sync-conflicts / maintain high-availability access to the most recent file, I sync the databse to a raspberry pi with the encryption option selected (not that the pi is untrusted per se, but it is a device that doesn’t need access to the file, it just serves the most recent changes to other devices since often my laptop / phone / desktop are not all on at the same time).