Q.I have a large Crinum Augustum plant
It had a huge amount of dead leaves in the center. I have removed much of the dead material. I can see new shoots in among the larger trunks of the plant. The leaves appear soggy. It does bloom, and soon the stem of the flower droops and the flower dies. I don’t know how to remove pups. I tried digging around one of the plants but found that difficult to not destroy the roots and still separate the one plant. I believe I am doing something wrong with pup removal.

It is a good idea to clean up around the base and remove the dead leaves and pups.
Regular watering, but allow the soil to dry between waterings.
Fertilize 3 times a years with a good quality granular fertilizer. Spring, Summer and again in Fall.
In my research I found that removal of the pups is easiest following a rain or watering.
Use a sharp, small shovel and get in between the mother and the pup and push down until you separate the pup.
Here is a link to refresh you on the care requirements.
https://www.gardeningknowhow.com/ornamental/bulbs/crinum-lily/crinum-lilies.htm