I will pray for your mother’s soul.
If I understand it correctly, you are now in possession of your mother’s ashes but because of financial reasons you are unable to afford the expense of burial or interment of your mother’s ashes?
If this is the case, I would reach out to the Catholic cemetery in your area or your Diocese to see if they can provide assistance with burial/interment.Often times there are programs to help those in financial need bury their loved ones. Regardless of the circumstances surrounding your mother’s death, burying the dead is a corporal work of mercy. Your diocese should be able to help.