Using Zitadel Cloud for Tailscale

I'm planning on using Zitadel Cloud for Tailscale. I'm just trying to understand the usage limits for the free account. I'm just a single person, but if I wanted to add a couple more users, I'm just trying to understand how the daily active users works. Like if someone logged in every single day, that means I could have up to three users, I imagine. I just want to clarify that because I was not fully understanding the documentation.