Reading is how native speakers of all languages improve vocabulary.
You did this in your first language.
I did too. We all did.
Remember that the AVERAGE American native speaker of English uses only about 400 words a day in conversation.
Tip: When you need to know the meaning of a new word from reading make a note of the word.
Keep a note book just for this purpose.
Look the word up AFTER you finish reading.
BECAUSE - The meaning will probably come in the next few lines.
This is called "context" and it is part of how we learn to speak.
No word lives alone.
All words live in context.
Use a dictionary in the language you are learning FIRST.
You already know your first language.
If you can't understand that meaning - use a dictionary in your first language.
This takes time but has great value.
When you use a dictionary read the two words before and the two words after the word you are looking for.
Your paper dictionary from long ago might be out of date.
Language changes. We do too.
Review the words in your note book after you finish reading.
Try to think of ways to use those words.
Then SAY them that way.
Today's One Point Wiki Wiki eXpression is "Look it up."
It means find the word in a dictionary.