Answer:
I am a portal to another world which you cannot enter. Only you can see me but I can't see you.
Light hides me and darkness kills me. What am I?
I can be short and sometimes hot. When displayed I'm never cold. What am I?
I am a popular afterlife location to send evil people
It rows quickly with four oars but never comes out from under its own roof. What is it?
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.