Can I get legal separation while living in same house? Wil I lose financial rights by moving out?

Yes you can be legally separated while living together. Also : there is no waiting period for a divorce.

No.

Pendente lite relief is in some ways based on needs. Going by yourself against an attorney is a serious mistake.

A marriage of almost 4 years ago is failing. She an immigrant and wants a divorce but he threatens deportation. Need options.

The threat is absurd. Ignore it

How do I protect my house from my ex wife after the divorce?

The question doesn't make much sense. If you were awarded the house presumably you know what form of ownership you have - and what needs to be...

Can someone please provide me a form for responding to interrogatories?

There is no specific form. This is one of the many reasons why litigating on your own against can be penny wise and pound foolish.

How can I see if my marriage is invalid?

You don't have to see - under those circumstances it *is* invalid.

My ex sent me a certified letter for expenses for first quarter of jan feb march. She sent letter not court or lawyer.

Your question is far from clear.

At the age of 7 my daughter was adopted by my parents. She is 19. I live in one state and she lives in FLorida.

If any attorney can help you it would be one in the state in which she lives.

Daughter 16 wants to live with Father as she does not want to clean her room, etc. at my house.

You can seek to have custody changed. Consult a local attorney.