My girlfriend has 3 kids and has food stamps . Is it safe to for us to get married so she can’t file for me , I entered the US legally

Given the facts as you have presented them, it may be difficult for you to pass the public charge requirement. If you have independent means of support, that may help. If you or your girlfriend have close relatives with US citizenship or permanent resident status, they could perhaps assist with co-sponsorship. On the public charge issue, USCIS will consider a totality of circumstances to determine whether you should be approved, denied, or required to post a public charge bond. Due to the limitations of the Lawyers.com Forums, Alan Lee, Esq.'s (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.