my macbook pro keeps says incompatible browser

Please post a link to the page you're having trouble with.

If its: www.fasa.ed.gov

You can try this:

Go to safari preferences, open advanced and check the box "Show Develop menu in menu bar".

Close the preferences and now you will see "Develop" in the main menu bar, open this and go to "User Agent" here you can select what browser script the web site might have been specifically built to show in. It's not unusual these days (Sadly 😟) for web designers not to take into consideration cross platform and cross browsers when building.

Hope this helps 🙂