Mothers Property share in daughters

There is a property which was on my mothers name who was not working. My father passed away 5 years back and mothere passed away in may 2019. we are 4 sisters and 1 brother. As per my brother mother left a will on which my father also signed as witness that my brother will be only one owner of the property. Though my mother wanted to build a will in which she wanted to give equal share of all her daughers and son but due to my brother force she couldnt do this . When my mother was ill my brother made a Family agreement on 1000 Rs stamp paper and asked me to sign on that . My 3 sisters signed on the same but me and my mother didnt signed on the same. Even I have not seen the will paper which my mother or father left for my brother as he didnt want to show me but continuosly he forced me to sign on the family adjustment paper. Now he has appeled in High court patna for Vortex for making this will in his paper. Now let me know can i file a title suit against that. I have the photo copy of the paper on which he wanted to take my signature. Please, suggest, Where and how I should file a title suit. in lower court or in high court. As he has filed this petition in Patna high court while the property is in darbhanga. Regards