uploading code on keypad lesson 11

lischiluarduino1:
I am new using arduino, having troubles uploading code on lesson 11 keypad. any suggestion appreciated. thanks. " if it helps this kit was bought through "ELEGOO"

I am too. Also using elegoo. it comes up something to do with keypad .h doesn't exist. it happened on lesson 10 too. Me and my dad dont know what it means.