Thereu2019s a few separate things here:OS and browser: they already have this as soon as you open the form. All web servers get this to ensure they can pra page you can load. You can send a fake one using something like the Google headers editor for Chrome, but itu2019s fairly pointless - you are just one of millions running near identical hardware. Itu2019s mostly useful for their site tester to check it works on the common platforms,Location: They will get a rough location from your IP address. You could use a VPN - they will still get a location, but it will not be very accurate. Locations from IP are often not very useful - often they are only accurate to the country level. The site might ask your browser for accurate location information - just click on u2018nou2019.Source site: Just open the URL manually in a new tab. Then there is no source site information to pass.Forwarded to site: They can only see this if itu2019s by clicking a link on the page. donu2019t click the links.Other sites you may have visited. Normally done with a cross-site advertising tracking cookie. Open the site in a Private / Incognito / Porn mode session to block them all. Close it as soon as you have finished.To be honest, they will get far, far more information from the form you complete than anything else.