listen I've been in this stage. I have thought of it and attempted and I'm gonna be 18 soon and you know what I'm so freaking glad I didnt end it... life could be shit.. you might have a horrible family, or no friends... but as long as you are not stuck between 4 walls there is always a way out.
There could be a guy who'd love you so much you'd forget all about your shitty family life and he will give you a new family!
I get how you hate everyone and want to leave everyone but do you really want to leave the amazing sun light, trees, butterflies and beautiful nature... because you can't be so sure wherever you'd go next would have those..
Read a book.... cherish the little things in life...