There are several ways in Windows 10 to switch between open applications:-

Desktop Mode

 

1)Press the following keys to cycle through all running programs

 

+

 

2)Click the relevant program icon in the taskbar at the bottom

 

 

3)Click the icon on taskbar and then click on the program you wish to switch to

 

Tablet Mode

 

1)Tap the icon on taskbar and then tap on the program you wish to switch to

 

2)Swipe in from the left of the screen - and tap the program you wish to switch to