I want to write a tragedy but nothing bad has ever really happened to me in my life...

How does a limbless man murder someone?

But seriously, that’s over the top to the point of being comical. It’s not tragic.

Tragic is falling in love and then dying before getting to enjoy it.

Tragedy is highly dependent on irony, or the clashing of reality and expectations.

What your premise is is simply the unluckiest guy ever. Is there even any conflict there? Sure, bad stuff is happening and he’s facing adversity, but is there any actual conflict in the literary sense?

Your premise also reminds me somewhat of Johnny Got His Gun, which is deeply tragic because the character wishes to be euthanized but can’t express the desire to anyone and certainly can!t act for himself. Again, it’s got dramatic irony in that he wants something but can’t obtain it. That makes it tragic.

You just need to be empathetic. It's probably better for the ex employee if you don't talk to him so read stories of similar events instead. There's plenty. Try to put yourself in their position and react. You're poor and about to lose your house... how would you feel? What would you do? It's an exercise in relating to situations on an emotional level.

Also how is he getting accused of murder with no limbs?

Do you think Andy Weir spent time on Mars? What about L R Hubbard? A lot of authors don’t have the chance to write from experience. What about all those authors who write about kidnappings and murders? Did they ever kill anyone? (Perhaps in a few cases). Writing is about channeling emotions and hitting those emotions during the right time. Learn to manipulate emotions with words. Practice writing these high emotional scenes. You don’t need to experience these terrible things to write about them. You need to identify the emotions, then use words to craft those emotions.

Something so big is easy to craft the emotion. And if all else fails, imagine it. The love of your life, your dreams, and hopes, your laughter and light is cheating on you. What would you feel? Even if it’s never happened to you, I’m sure you could imagine it. Then magnify it, add tension and suspense, sprinkle in some purple prose, and poof. You’ve got emotion. And you didn’t even have to experience the actual heartache.