ES has given good advice, they are easy to grow, they like benign neglect!
I have about a hundred clivia of various colours.
https://i.imgur.com/Y9sCYvw.jpg
https://i.imgur.com/Svofl8f.jpg
https://i.imgur.com/xJc2h58.jpg
Your plant looks very mature and would have bloomed some time ago looking at the size of the berries. The spike with the berries could stay on the plant for over a year, Ive seen plants in full bloom with the berries from the previous year, a stunning look.
If you don't want to grow those berries on you could remove them and the spike will dry up naturally, once throughly dry the spike will pull out easily.
Growers don't usually try to remove the stem when green as sap rises and could make it damp in the centre of the plant and cause rotting.
Also be aware some people can be allergic to the sap.
If you do decide to grow the berries on to seedlings wait till the berries crackle when rolled gently between fingers. Berries may even change colour depending on what the colour the blooms were.
Then the berries will need to have the cover and flesh removed, berries can have anything from 1 to 8 or 9 seeds inside.