You won't find any automated way to delete a Roblox account on its website. Use one of the 3 methods listed in the post to delete Roblox.

You can delete a Roblox account by simply emailing the company, but there are a few other ways to do it.

Now Roblox should have no problem installing on your PC! In the event it doesn’t, double-check that you don’t already have Roblox installed and, if so, remove it for a fresh installation.