50 moves

# end game

Not in fact.

It's at most 75 times the number of moves for each of your pawns to reach its promotion square plus 75 times the number of pieces you have in addition to the king, but your opponent may optionally claim a draw after at most 50 times the number of moves for each of your pawns to reach its promotion square plus 50 times the number of pieces you have in addition to the king.

That's under FIDE competition rules. Under the FIDE basic rules you can carry on moving till one of you dies (from 1st. July 2017 to date) so long as the position is not dead (or already mate).

how many maximum moves i can do officially i got to win when the opponent has just the King?

How many moves until the draw game

thanks in advance

Mattek73