I want to lock session when I'm not on my computer with the press of a button or touching the corner of a screen with a mouse. Once locked, it should go to a lightdm screen. I've heard of slock but I don't think it can do what I want to do.

Also on that note, how would I go about locking session automatically after like 10 or 15 minutes? All the resources I read were pretty old and didn't really help at all.