Go commit self deletus is one of the hundreds of roblox memes published to the internet. Its also used as a (poor) comeback to some insults including ur mom gay lol (the ultimate one shot kill insult(the only comaback for that is no u)).
commit self deletus means go kill yourself (as you can probably tell). some other similar memes include,
go commit toasterbath, go commit die, go commit death-pacito, go commit neck-crack-bone, go commit waterbreathe, go commit knife-heart, go commit no alive, go commit tower jump,
go commit uninstall life, and go commit scooter-ankle.
This is Yeetus yeetus commit self
deletus being used as an attempt to make a comeback from "ur mom gay lol" and "no u".
Person 1: ur mom gay lol
Person 2: no u
Person 1:
go commit self deletus
Person 2: go commit toasterbath
Person 1:
go commit die
Person 2: go commit waterbreathe
and so on...