If Roblox is not downloading or installing on your Windows 11/10 PC, restart your PC and if that doesn't help, use the fixes discussed here.

Now, find the Roblox folder in the opened directory and double-click on it to open it. After that, right-click on the blank space in the folder and select the New > Folder option.

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.