Close any programmes or tabs that aren't being used. Open apps are shown by a little dot directly below the app's symbol in the bottom toolbar of your screen. Simply right-click the programme and pick 'Quit' to close it off.

Configure your Mac to start up with fewer programmes. Select 'System Preferences,' then 'Users and Groups' from the Apple symbol in the upper left corner of your screen. Next, toggle over to 'Login Items' and check the 'hide' box next to the apps you don't want to launch each time you turn on your Mac or restart. You may have to go into the settings of individual apps and disable the auto-launch with the restart function.