One wrong move
Retract the move and enter the correct move. Click Overwrite in the variation window that appears.
Retract, hold down the Shift key and enter the correct move.
Retract with the express retraction button and enter the correct move.
One wrong move in the middle of the game
Click on the move before the wrong move in the notation, enter the correct move and click Insert.
Wrong line in the middle of the game
Enter the correct moves as a variation. Click Insert – Variations – Exchange moves. The moves of the variation replace moves in the game. Naturally all the rest of the moves must be legal, otherwise they are cut off.
Missing moves in the game
Click on the position before the missing moves, enter the move pair or pairs (always an even number of moves) as a variation. Click Insert – Variations – Insert into game.
ChessBase will insert the moves and add as much of the rest of the notation to it as makes sense.