Hello! Start by researching your family history and gathering relevant documents—especially from relatives born in Lithuania before 1940. You'll need to prove your lineage and show they were Lithuanian citizens. I highly recommend you to contact a company like DE Civitate Group to obtain lithuanian citizenship by descent https://www.lithuaniancitizenship.com/lithuanian-passport/ . They handle everything from eligibility checks to submitting your application, making the process much easier and more reliable.