How do you check your level on Black Ops?

There is not one person who is a level 50 top level prestige, ignore them.

If you have the 360 version you check in your combat stas (I think) in the player card section, not sure if it the same for the other versions,

They are talking about the Online Multiplayer mode, if you haven't tried it yet, you are currently a Level 1. You can rank up by getting kills online, completing contracts (Which you will find more about later), completing challenges (Again, it will explain later), completing objectives (Capturing flags, planting bombs, securing headquarters, ect).

Try multiplayer mode, it's really fun. If you aren't ready to face real people, you can try Combat Training in which people are simulated by bots. You can select the difficulty of the bots, Recruit (Easy), Regular (Normal), Hardened (Hard), and Veteran (Very Hard). You can earn weapons and Call of Duty Points (Which you buy stuff with such as Weapons and Attachments) seperately from Xbox LIVE or PSN in Combat Training.

Hope this helps!

Those people are playing Multiplayer. To check your level, you must have XBOX Live or PlayStation Network. From the main menu, select 'Multiplayer'. You should see an option that says either 'XBOX Live' or 'PlayStation Network'. Select 'Player Match'. You should see your level next to your XBL / PSN name, it would have an icon next to the number.

theyre probably playing the multiplayer mode, and ur on single player doing the missions. Theres no way to check ur lvl unless u play multiplayer and lvl up ur guy on it.