I can't delete windows completely

I had a number of errors in windows, so I decided to reinstall it, but I forgot how to remove it, so after looking on the Internet how to do it, I saw that it was possible through the disk utility, but with its help, the windows volume was not completely deleted, when restarting the laptop and clicking on option, the windows volume is still displayed. I had to delete it via bootcamp, but I didn't do it. Tell me, how can I completely remove windows?