I start the game as normal and play mission Cesar Vialpando. But then, when the man told me to enter the garage in WIllowfield, the garage didn't open! No matter how much did I try, how hard did I smash the wall, the game's still not allow me to enter it, I need suggestions from you guys :(( P/S I'm playing Gta V San Andreas mod

Post on the game's forum http://www.speedrun.com/gtasa/forum

I'm sure there's a Discord too

This is a speedrun site, not a modding site. For that bug, go search for the correct site where it is made and ask in the right topic. They can help you better than us.

Have you tried speaking the elven word for "friend"?

Well, I'll ask this on forum then

Not on the speedrun forums of gta:sa. You are using gta5, not sa.