Msx Roms Sets How To Patch A MSX ROM?

How to patch a MSX ROM? - msx roms sets

I want to play rom of Metal Gear for MSX. But the game is japanese.There this site, which carried out a patch for the game in English, but I do not know what a ROM patch. Can someone explain step by step, so I can understand (im a n00b) coil. This is the website with the patch: http://www.geocities.com/nekurahoka/

Thank you in advance.