Some printers can connect directly to your pc
All Wi-Fi enabled printers can be part of a network using your ROUTER for its connection
If yours only works when your hotspot is turned on,
Then it is setup to use your hotspot routing
If you want to print from more than one specific device then you need to use network routing
If you only want to print from one pc, you can TRY to setup a direct pc to print Wi-Fi connection
But then the pc might not be connected to the hotspot for internet
When Wi-Fi networking was designed
The design operation protocols aka instructions and limits
Were setup for using a router to connect everything together
Not for a printer or pc to connect to multiple devices at the same time
That was is the job of the router
An access point by design is router allowing multiple devices to connect to the network and accesses other devices such as printers