http://y7yea4pmqqtznb33qiugvysyn2bob5v62e4pvoadoibrwkq3tsddjeyd.onion/zh-hans/module/how-delete-your-data-securely-windows
Unfortunately, due to the way SSDs, USB flash drives, and SD cards work, it is difficult, if not impossible, to securely delete both individual files and free space where some operating systems may leave parts of files. As a result, your best bet is to use encryption . That way, even if the file is still on the disk, it will look like gibberish to anyone who gets ahold of it and can’t force you to decrypt it.