Endnote question reference in word

I have a question about how to refer by using APA.

I would like to refer in word as (World Health Organization [WHO], 2018) 

for the first time.

The second time I would like to refer as (WHO, 2018).

Does anybody know how this works?

Thank you in advance!

you should enter the author in the record as World Health Organization [WHO],  (note the trailing comma) and for subsequent cites, you will need to edit the citation hide author and manually enter “WHO”.