Also, thank you for the many responses!
I am plugging in an XLR microphone Apex 435 condenser mic. When I turn on the Phantom Power button, I get it lighting up, so power is getting through ( I had to buy a replacement Behringer UB1002 Xeynx power adapter).
Unfortunately, I have noticed that I am not getting any power lights or level lights for the MAIN SECTION.
The mixer I have looks like this (I gave the wrong version of the mixer in the description, sorry about that - it is the UB1002 Xeynx):
View attachment 104302
I am wondering if there is something wrong with the actual mixer because of this. Power is flowing through it because of the Phantom power working, but the POWER button and LEVELS (when using the mic, screaming into it ) do not light up.