i man how to dumps works? are they by codes? or something you can add or does it only work through your disc.
A dump is a copy of a disc. The ISO file that you have is your dump of this game.
If it isn't clear yet, to get Dolphin to calculate the MD5 hash of your dump (the Compute button) use the latest revision of Dolphin. 4.0.2 is not the latest. Just download the first thing you see here:
https://dolphin-emu.org/download