1.) How to make custom user title?
2.) How to put post background?

To put an image as a background for your post, you need either VIP or ToriPrime. Same thing for custom user tittle.

Click that "UserCP" link on left, and you see that bar on the left and click "Edit Your Details" link, and you'll see that custom usertitle thing.
And you can't use BG images without VIP.

Just as a reminder, VIP can only be bought when you ALREADY HAVE a ToriPrime subscription.

So, its like an add on to Toriprime?

You must first purchase Toriprime to be granted the ability to purchase VIP, which costs 7 USD and allows you bigger sigpics, avatars, access to a secret board, and a username prefix. As Danzos stated above you can change all this through the User CP in the selections 'edit your details' and 'edit options'.

Yes it is like an add-on of ToriPrime, only it allows you to search, have more gfx features, and access to the VIP board.
Just as Facade postes above, and this is the reason why ToriPrime costs more than VIP.