How to draw in a section of the screen

Newbie & Debugging Questions
#1

So, here’s my little game frame thingy.

Basically, Where the purple/pink is, is where I want to draw my actual game.

I’m using LibGDX and I’m going to be used a TiledMap for this, but I’m not sure how to only make it draw in that section of the screen.

Any ideas? I already have the bounds for the box.

// X 150 -> 1000
// Y 720 -> 180

Just not sure on how to go about creating that area to draw in.