The way to ask politely for a glass of wine in a spanish-speaking country is the following:

'Me puede poner una copa de vino por favor?'
'May I have a glass of wine please?'

This is a list of drinks translated into spanish that you may want to order in a restaurant or bar:
-un vaso de agua (a glass of water)
-una botella de agua (a bottle of water)
-una cerveza (a beer)
-una taza de te (a cup of tea)
-un cafe (a cup of coffee)
-un zumo (in Spain, a bottle of juice)
-un jugo (in Latin America, a bottle of juice)
-una botella de vino tinto / blanco (a bottle of red / white wine)
-un agua con gas (sparkling water)