Feel worthless

I'm a software engineer. I feel so worthless of myself that I feel like hurting myself and ending myself. I fuck up every job interview by getting nervous. I get afraid and struggle to put my thoughts together. I get rejected all the time. I feel no matter how much I prepare, I fuck up. I feel stupid and worthless. I have lost confidence in myself. I am overweight as well, have disgusting belly. I feel like a total loser.