Restore Firefox icon removed by mistake from the screen I don't know how I did removed the firefox app icon from the main scren

How can I restore it?

My phone is using Android 5.1 and it is a TPLink Neffos C5

Edit:
The icon is not present in the app drawer



But at the applications section
As unusual, my phone does not support app drawer, but it comes with a feature named Hidden apps, the solution was:


Access hidden apps by doing a 2-finger swipe on the home screen.
Search for the firefox icon and add it to the hidden apps.
Close and reopen hidden apps.
Press edit and unselect the icon.


Now it should appear at the end of your screens.