How to combine mods?

[Ehil7 1]

I'm going to publish a second mod that should complement another mod, but I don't quite understand how to combine them.

I had plans to add wonders of the to the new mod and rename the provinces, but when I do, they are not added/replaced with those in the original mod, and, accordingly, they do not appear in the game. Do you know how to fix this?

[Iceman 295]

There can't be two mods modifying the same files, and the files in the mods folder only overwrite original game files, not from other mods.

[YouravaragebrazilianAoCfan 293]

Make a variation of the mod with the complementary mod in it instead of making it a dependent mod