I am not sure that I understand your question, but I will try to answer. To truly learn a language at a useful proficient level, you need to be able to do the following:
Read an email or document and understand most of it.
Speak spontaneously on ordinary topics
Listen to someone speaking to you in person, a person on a phone, a TV show , and a radio program and understand most of it.
Write on common subject matters.
To do this, you need to study with a teacher, study partner, and native speakers, you need to write compositions and have them checked, take online exams, watch TV programs and listen to radio programs.
I would add that it is difficult to know every single word that you read or hear, but you should know enough to understand most of the conversation.
You should also add regional sayings and slang to your studies once you have begun to master the language.
I hope this helps.