After you enter your FTP credentials, you will need to Select Folder With WP Installation.
Step 1: Find the public_html folder. It’s where WordPress is installed on most web hosts.
Step 2: Select it and hit Apply Fix.
We have created a few quick videos on how to find WordPress Install Folders DreamHost, SiteGround, 1&1, Hostgator and GoDaddy. Please take a look.
Quick tutorial on how to find WordPress install folders