How can i turn off goverment changes so when i make a scenerio they dont change???

can't you just delete all the available governments except the ones you want?

Then they would still change among those left.

What you have to do is to give the government tech to only those civs that you want to be in that government. Then make the cost for the tech very high so the other nations wont research it.

Thread moved to Creation & Customization

You'll get a better answer there.

Put the governements in non-era tech, make them untradable and gives them to whatever civs you want.