Sterilization also called tubal litigation is a surgical process where the fallopian tubes is closed or cut to prevent pregnancy permanently. This prevent the egg from reaching the uterus and hence no fertilization ever takes place. This is an irreversible procedure and it is important to consider all options and discuss it with your health care provider before going through with the procedure.
Sources: https://www.webmd.com/sex/birth-control/birth-control-sterilization
https://www.britannica.com/science/sterilization-medicine
https://www.nhs.uk/conditions/contraception/female-sterilisation/
https://www.plannedparenthood.org/learn/birth-control/sterilization