Can a landlord of a commercial property in TX send you a text demanding you vacate or be vacated without any prior notice given?

This question has already been asked and answered. I suggest you either look to those responses or seek direct consultation with an attny rather...

Can I evict my brother from my home in Texas?

Likely he could claim tenant status and you would be best served by following formal eviction process.

My landlord is charging a legal fee even though I am not being evicted. He said he was tired of people moving out and him paying

You have not provided enough information to give an opinion. Generally this sounds suspect, the deposit is ment to cover a LL for unforseen stuff.

The question all revolves around what status the court would see them as having... guest, tenant, etc. If they are guests they could be excluded...

Rent is 625 a month...paid 300...can landlord file an eviction?

Yes if rent isnt paid in full, on time the LL can file for eviction.

What is landlord's right when tenant gives a 3 day notice but does not leave on the 4th day and this is in Texas?

If the tenant has violated the terms of the lease the LL can seek eviction, however if the tenant hasnt done something they said they would (but...

What can I do ?

You can force them to evict you and then show the court that you have fullfilled the agreement terms and they have not. Likely you lease allows...

My family and I want to evict the tenants who have not paid or signed the contract? What can we legally do?

If they have failed to uphold the agreement (written or verbal) and you can show it then you can begin eviction process. If there is no written...

Am I able to press charges and/or sue the landord that assisted my roommates (the prime tenant) in an illegal lock out?

If you are not on the lease as a signer or occupant it is likely they will get away with putting you out. Most leases require written LL approval...

Not on their property

You have not even asked a question here. I suggest you gather your thoughts, provide some background info, and ask your question.