Web page will NOT go away!!!

Im going to try my best to explain this, and attach a screen shot below... I went on a website and a sign in box popped up saying "to view this page you must log in to area" then it has the places for me to login. The problem is that its a random website I went on to look at yarn colors of all things and I do not have a login. So the "x" circle is greyed out so I can not close the window and when i force close it goes away but as soon as I open safari again it is still there. I have went and deleted whatever keychains that i was unsure of what they were, i restarted my computer, reset safari, cleared out cookies, deleted history. Im not sure what to do now. Please help!

Quit Safari fully (so there's no blue dot beneath the icon in the dock).

Hold Shift and click the Safari icon to launch. This should prevent the last page from restoring.

Thank you so much!

If you get one of those password dialog pages again, you can simply push the escape key on your keyboard which will cause the password prompt to close. The resulting page won't load but since you don't want that page anyway, you can simply push the back button in the browser and continue on your way.