All started when I got messages from google that some of my sites might have been hacked, I check the webmaster tools but they didn't have any specific info.
In google analytics I saw that some of my sites were getting more than what they used to organic traffic and when I checked it, the landing pages of all this traffic were some irrelevant pages that I had never created myself and when I go to see what they look like they don't actually exist. Even though they don't exist when I make a google search I see that they are indexed on google (check the screenshot)
I tried to see if I can find these pages via the file manager and the databases on phpmyAdmin on cpanel and even though I found some strange pages on the databases and I deleted them the traffic to these no existant pages continues coming. The status of these pages was "test" which I have no idea what means since they didn't exist on wordpress.
Additionally all this time I was getting a tone of user subscriptions on wordpress and even though I deleted most of these accounts and after a few plugins I stopped them when I go to see these accounts on wordpress a huge number appears without however any account existing (check one of the screenshots)
I watched the videos on google with the steps for cleaning a site but they don't really apply to my own problem since they are not showing any similar problem...
I really don't know what else I should do since I did most of the things that are suggested when a site gets hacked (changed pws , added more security plugins, removed any strange database and content via cpanel etc)
Please help me