ok yess but he cant join its not letting him

ok so i press f10 and i dobble click on his name but nothing happens i join the discord server and i still cant get help

ok yes but how do i inv them

he did its just when i load up zombeis make a solo game and i press friends its says i have no friends

how can i invite my friend to my game and also how can i add them someone help plsese i realy want to play with them i add them but when i go and load up the game it says i have 0 friends so can someone pls help i would realy like to know