GSM-MMS SIM900

Hello guys, first i'm not english so i'm sorry if i'm doing mistakes!

So i'm asking to your help because i want to "create" a smart mail box! who is sending you a picture two times a day and if you asking to it to send you one (to see what is inside the box)

That the point! i'm using a sim900 and i looking on the web for 3days maybe more to know how to use it !

I'm a truly beginner on Arduino etcetc (Btw I'm a high School student) So there is (finally) my question :')

How can i do to send a Text and receive a MMS?

And

How can i do to set a delay like every 5hours a MMS is sending ^^

That would be really thankful if you answer to my question !

have a look at Sending an SMS message