Among them The Spaniards counter at opening serving brews up ...? (4)
I believe the answer is:
pubs
'among them the spaniards' is the definition.
I can't tell whether this definition defines the answer.
'counter at opening serving brews up ?' is the wordplay.
'counter' is a reversal indicator.
'at' becomes 'up' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'opening' indicates taking the first letters.
'up ?' says the letters should be written in reverse (in down clue: letters go upwards).
The first letters of 'serving brews' is 'sb'.
'up' written backwards gives 'pu'.
'sb' backwards is 'bs'.
'pu'+'bs'='PUBS'
Can you help me to learn more?
(Other definitions for pubs that I've seen before include "Inns, drinking places" , "Taverns" , "Hostelries" , "Locals" .)