You should be able to do that using the internal WiFi on the mini-PC, but you can also use an external dongle to do it.
I have used either approach and both work. I usually use a dongle to create the external hotspot as a backup, just in case I get frozen out by my Pi4 on the internal network.
I have also used the travel router, but if you are out in the dark, that is just one more thing that consumes battery power.
All of these solutions work.