How can I check if my CB radio is AM or AM/SSB? I know that it is a CB UHF radio but there is no information of whether it is AM or AM/SSB.
As mentioned in another answer, it sounds like it’s not SSB. The next question is whether it’s AM or FM.
“CB” can mean different things in different countries, and you don’t say which country you are in. But you say that it’s UHF - and FM is a much more common mode to use at UHF frequencies (and even at VHF) than AM.
If it were SSB, it would usually have a switch to select USB or LSB, and it would need a clarifier, or a full VFO.
Australia has two CB bands, the old 27MHz band, where radios were either AM or SSB, & the UHF one, which uses FM.(which is apparently, the one you have.)
Other countries have variations in either the band or mode of their 27MHz CB operations (27MHz FM is common in Europe), but although many have "CB like" frequency allocations at UHF, Australia & NZ seem to be the only ones where there is a band officially designated "CB" in the UHF region.
If you should come across some 27 MHz CB radios, you can tell if they are "SSB/AM", or "AM only",by looking ar the front panel controls. An SSB radio will have a switch with positions marked "USB", "LSB " & "AM", & a variable control marked "clarifier". An "AM only" radio will not have these controls.