my lg stylo is locked on google sign in

I have a used LG Stylo phone I bought on Ebay. The seller did not tell me his username or password. I have looked everywhere on YouTube and nothing is available to fix this issue. Either I don't have the button (greyed out) etc. Any ideas what I can do? I can get as far at the Google Sign in page. Please help. The buyer won't help or return my money.

I cant get passed by the Google account bypass