Hello AnitaRH and welcome to Apple Support Communities.
I see you are getting an error message typically associated with cookies in a web browser.
Are you getting this error message on all sites or only a a limited number of sites?
Typically, this error message means that the site you are trying to access requires a cookie to load. Try going to Safari > Preferences > Privacy. If the option to block all cookies is enabled, turn that off and try loading the site again.
If that option is not selected, the click the button called Manage Website Data and scroll through the list until you find the site you are trying to access. Once you find it, click on it and then click the Remove button in the lower left. Then, quit Safari, reboot the Mac and try loading the site again.
Manage cookies and website data in Safari on Mac - Apple Support
Cheers.