Im doing a thesis statement on ADOPTION , and i wanted to know if mine was good so far.. : The majority of states (34) of them , lacks statewide legislation , case law or department regulation addressing adoption!

That's not a thesis statement yet.

Your thesis statement must include factual information (which you already have) plus your position/opinion/stance. Without your position on the topic, it isn't a true thesis statement. So think of this sentence as the angle you want to take on the topic and what you intend to prove by the end of your paper. (If your statement is simply factual, then there's nothing to prove!)

http://blog.eduify.com/index.php/2009/06/21/5-tips-on-how-to-write-a-strong-thesis-statement/
Read carefully and follow ALL directions.

http://leo.stcloudstate.edu/acadwrite/thesistatement.html
This is one of the very best places I've seen online to help students write good thesis statements. It shows you sentences that aren't thesis statements and how to turn each one into real thesis statements.

Your thesis statement provides a clear and factual statement about the lack of nationwide legislation, case law, or department regulation addressing adoption in the majority of states. However, it would be beneficial to further develop your thesis statement to explicitly mention the significance or implications of this lack of legislation. Additionally, if your thesis statement is going to be the central argument of your thesis, it is essential to provide more specific context and directions for your subsequent research and analysis. Consider revising your thesis statement to address these points.

Here is a revised version of your thesis statement:

"The lack of comprehensive statewide legislation, case law, or department regulation addressing adoption in the majority of states (34) not only reflects the legal gaps and inconsistencies in safeguarding the rights of LGBTQ individuals but also underscores the pressing need for comprehensive reform that ensures equal opportunities for prospective adoptive parents."

Remember, a strong thesis statement should not only make a claim but also provide direction for your research, analysis, and argumentation in the body of your thesis.