1. Go to the Google Account Security page on any browser.
2. Scroll to the "Your devices" section and select Manage all devices.
3. Choose the public computer's session or the generic "Browser on Windows" or "Browser on Mac" entry.
4. Select Sign out.

if you don't have a Google account you an go to another account that is connected to all the device

here are more tips for no Google account 

1. Open Facebook and go to Settings & Privacy > Settings.
2. Select Security and Login (or Password and Security).
3. Under the "Where you're logged in" section, you can select See All.
4. Find the session on the public computer and click the three dots menu, then choose Log Out. 

1. Go to the Apple ID account page and sign in.
2. In the "Devices" section, find the public computer (if it was a trusted device).
3. Select the device and choose Remove from account.

did it work