No Electricity To One Room

One room of my home has no electricity. There are no GFCI outlets in the "chain" of things, and the breaker for this room is not flipped.

I have tried to flip the breaker, then turn it back on and nothing. What other things would I need to check to determine why there is no power in this room?

EDIT
A Ubiquiti Access point was added to the room for better wifi coverage, but that is the only 'change' in the past 8 months that has taken place in that room. All outlet wiring runs behind the wall,

I have this Klein Tester – should i pull out the outlet and check for 'hot' wires? I have checked all outlets with this Klein Outlet Tester and no lights turn on.

EDIT 2
As suggested in one of the answers, I checked the last outlet on the chain (I checked the last two as I wasn't 100% sure which one was last) and visibly didn't see anything that looked awry. I checked the first outlet on the chain and this one is using a backstab. It has 3 wires, 2 connected to the screws on the side and one connected to the backstab for both the black and white wires.

What is still throwing me is even if I use the non contact tester and check the wires connecting to this receptacle, none of the wires are still showing up as hot. And I am 99% certain this is the first receptacle in the chain. Should I test the breaker in the box to see if that is the culprit? (if yes, will the voltometer I have work for that)

EDIT 3
After using the pen tester to test the breaker it is lighting up red, (all the fuses were lighting up red) which would mean that the breaker has power and the issue is downstream, correct? (like stated in comments maybe a junction box that is either a in the crawlspace or somewhere in the walls…how the world do I trace that?)