I have a computer Mac, and I enter in the module, so that it can unlock, but I cant not write does not accept letters, numbers or symbols, and asks me is waiting for root device, what can I do....

Some more details will probably be required. The OS X version will help, as a start.

If you have the diagnostics DVD disk, boot that and see if there are any errors logged.

If this is OS X that's installed on a MacBook Air that you're using, then some of the usual triggers and approaches for resolving the still waiting for root device errors are discussed here. Have a look at that, and see if something in that sequence looks familiar, whether the PRAM reset or the safe boot helps or works here.

If there's any anti-malware, I/O accellerator, antivirus tools or similar installed, get rid of it. At least for testing.

There's a mention of "other OS" in your footer. If not OS X, what is the operating system in use here? If this is some other hardware or software involved, then the triggers for this error can vary. Widely.

Lastly, if you are using a wirless keyboard/mouse for non notebooks, find a wired keyboard and mouse in case there is an issue with bluetooth. Might be handly even for noebooks, if things are too bad.