Ok for this 22%, but is it from training or you can get past that in combat? And what 22% means in fact?
It is from training, and will accumulate slowly over time even if your ship is not actively under a training admin command. The 22% means that your crew will perform certain tasks better - specifically it affects beam weapon to-hit chance, missile reload rate, and rate of maintenance failures. The crew training bonus of your commander (at 50% effectiveness) and executive officer, if any (100% effective) help you gain this faster.
(Incidentally, the reason it maxes out at 22% is because the formula is SQRT(crew_grade) - 10, and crew grade can vary from 0 to 1000 points.)
There is a separate Fleet Training modifier which is maximum at 100%. This affects how quickly a ship will respond to orders, most importantly orders to open fire or change targets. This is the training modifier that fleet training (for ships under a TRN admin command) improves, although I believe it will slowly improve on its own regardless (not sure though).