Questions & Answers about Normalmente vamos a la playa.
How do adverbs ending in -mente work?
Does normalmente have to go at the beginning of the sentence?
No, adverbs of frequency are quite flexible in Spanish. You could also say Vamos a la playa normalmente. Putting it at the beginning is just a natural way to set the context for how often the action happens.
Why isn't there a word for 'we' in this sentence?
The verb vamos already means 'we go'. In Spanish, you can almost always drop subject pronouns like nosotros (we) because the verb itself tells you exactly who is doing the action.