I am in litigation and am currently living with family and have a two year old. My soon to be ex's attorney has sent a letter

The judge cannot even read whatever is sent to him in the form of a letter. I would disregard this and move forward with your litigation.

This means that the matter is pending assignment. It usually takes between 6 and 12 months to complete an uncontested divorce in Brooklyn.

How do I go about getting custody of my 12 yr old son who I feel is unsafe in his mothers care?

As my colleagues stated, find an attorney and file a custody proceeding. A quality attorney is essential here. Speak to as many as you can and find...

I am in a bad situation. I have a toddler and my court case is scheduled for trial. My soon to be ex is not responsible and

As little as possible considering your fact pattern. If I were you, I would be opposing overnights and insisting on day visits only.

Me and my mother don't get along what so ever. I would like to move out but im only 17 years old.

Simply move out. There is very little that your parents can do.

Can I file for Child Support from my Ex-Husband if we still live in the same apt due to inability to find stable housing

You cannot file for child support if the two of you reside together.

Can I petition for a rental property that my Ex-husband and I share if both of our names are on the lease

What do mean by "petition"? If the two of you are divorced you should not have any joint property and if you do, then there is a problem.

Contempt

There is no way to answer your question as the very specific circumstances of your case are more than you can state here. You may need to insist...

Can I evict my Ex-Husband from the rental property if his name is on the lease

My colleague said it very well. Also, if there is nothing in your divorce judgment then you may need to speak to your landlord to start an eviction...

What does it mean when CPS says there going to flue a deem order

Your question is very unclear. I suggest, if you have attorney, that you ask them.