Updating drop down list as custom field

a wonderful good morning lads!
I am creating a stock list at present.
also I am creating a suppliers list.

when adding in stock, I want to be able to pick a supplier from a drop down list.
Is it possible to stick in an interactive drop down list that automatically lists the current suppliers?

you need to explain better what you want to achieve.

what are you trying to do? where are you trying to do it?
some screenshots may help to better understand.

No, you can’t interlink other tab listings.