Souls in purgatory cannot pray for themselves. That duty falls to us. Deacon Michael gives us four simple things we can do to assist the souls in purgatory:
During the 7 days following All Souls' Day there is a plenary indulgence applicable to the souls in purgatory when you visit a cemetery and fulfill the necessary requirements for a plenary indulgence: https://seton-parish.org/plenary-indulgences-for-all-souls-week-and-the-month-of-november#:~:text=Visiting%20a%20Cemetery%3A%20Visiting%20a,only%20mentally%2C%20for%20the%20departed.Pray the Rosary for them.Have Masses said for those who have passed away.Pray St. Gertrude's prayer: https://prayforsouls.org/ways/prayers/st-gertrude