To link your website and MLS to your Facebook Business Page navigate to the 'About' Page. 

It will be on the left hand sidebar menu, under the 'Home' tab. 

Once you have navigated to the 'About' Page, scroll down to the bottom until you see 'Website'.

You can then click on the blue pencil with the word Edit next to it and enter in your Website links. You should be able to enter both your personal website and your MLS link.