[Vehicle Mods]

I have a question about vehicle mods, yesterday I saw a guy driving a skyline. It is this possible? I can replace any car and everybody is going to see it? How does it work?

[Player nationality]

Hi everyone, im really interested in gta roleplay nowdays because it attracts me, but my cuestion is the following: Im form South America (Uruguay), so I would like to know if in this server are many people playing that speak my lenguage or if it possible for me to play anyway.
Thanks