I thought similarly when I was severely depressed. The world would be a better place if there were no living organisms, hence no suffering

My conclusion now is:

You can’t kill every living organism to end this suffering

Even if you managed to do so, they would come back because of evolution

You can’t escape from this cycle of life and death whether as a human or other organisms. Hence you can’t escape suffering even if you kill yourself

So, it’s best to live a life trying to “reduce” your and other’s suffering as much as you can. This is my stupid philosophy. Hope you get better mate