Steam – cant stop Steamclientbootsrapper from running and I cant delete steam! Help!

One day, not long ago, my Steam wouldnt start anymore and I thought I just needed to restart my PC. After 5 times of restarting and trying to open Steam, I searched for help. I tried many things, and at the end I tried to delete Steam. I deleted about half of the files, because most of them were running in the background. I didnt know that before just now, so I couldnt delete Steam, open it or anything else. And I cant even find steamclientbootstrapper. I cant find it in the task manager or anywhere. I cant delete Steam since my Steam starts up when my PC does, and then I cant download steam again from Steam setup because Steam is already running in the background. And I cant stop Steam from running…