Here are the definitions. I think you can figure out bottle-opener and beer-drinker from these:
An endocentric compound consists of a head, i.e. the categorical part that contains the basic meaning of the whole compound, and modifiers, which restrict this meaning. For example, the English compound doghouse, where house is the head and dog
Both of them are definitely endocentric. 'Bottle-opener' and 'beer-drinker' are compounds which grammatically belong to the same part of the speech as their head word and carry the basic meaning of the head word:
'bottle-opener' - a noun; the head word of the compound - 'opener' - a noun (an opener which removes bo