My enter, backspace, down and right arrows not working

Hello,

I'm having this problems lately and it bothers me a lot because I needed to do my assignments and stuff. Sometimes it just back to normal, sometimes it's disabled back. I tried a lot of methods, recovery, turning off toggle keys etc, as many of the ones that I found in the internet suggested. I dont think it's keyboard failure, must've been what I've pressed accidentally but I don't know what it is. Please help me before I crash my laptop :(