Help to re-size browser

Was on putlocker to watch an old episode of UK 'Happy Valley',
next day found some of my 'Favorite' sites had been re-sized as below:



how do I get the info part of the page back to edge to edge ?

 

go to the top right click on the thing that looks like a gear then look for zoom and adjust size

 

thanks Very much hmcp, now sites are back to normal