I have a theory where you start with mainly vocabulary, rote learning like this is a door, this is a fridge, this is a cat etc... You can make it fun and varied but it's just rote memorization. This includes set phrases too like how are you and even set dialogues etc, but all without really understanding the grammatical underpinnings.
The next stage I think is the grammar stage. At this stage you learn how to put the words together into meaningful sentences. Grammar is what makes the words really mean something other than just names of things.
The third stage I think is the style stage. This is where you need to learn how to add nuance and to understand nuance and subtext in the language. This is through lots of direct speaking, reading and listening.
Through all three levels of course you continue to learn new words and this never ends, even in your first language.