Hi Sonam,

I have also the same issue in completion of my trailheads that i have to create a lightning page and in my org lightning app builder is not enable.
Could you please enable it to my org ID
My Org ID : 00D28000000XRoSEAW

Hello All,
            I'm using developer org and I want to develop an lightning app.I just have a option of "Lightning component" so that I wanna know that do I need "Lightning app builder " Is yes thn how can I enable that option?