Please help

My head is filled with many thoughts and there are giving me depression. And it is torture to me. If I just say one of the main thoughts that makes me down, is about death. I just try to not think about it because I know I can’t do anything about it. But it disturbs me so much by the thought that there isn’t much time left. It is like less than 3000 weeks. And my life is filled with regrets and I tried to be good from now on but the depression stops me. And I’m very by the thought that these happy days won’t exist even though it just felt usual and forever. And I can’t stop thinking that in the future I won’t be like I don’t want to die in the future. It will be I am dying. I’m so depressed I don’t even know how to be happy now.