Make a habit of listening to podcasts and audiobooks in the English language. Read books, articles, and blogs in English and write the troublesome words on a sheet with their meaning.
Find out a new word daily and practice it for a week to fit the word in your mind. Pay close attention to learning phrases and idioms too.
Watch English drama, movies, and shows; pay attention to the pronunciation and body language of the characters. Use subtitles, and patiently move yourself off them.
Use pronunciation tools to learn correct English. Practice expressing the words in front of a mirror; record yourself to track the efficiency of your learning.
Whenever you find yourself in a quiet place, start talking to yourself; this will build confidence and overcome the fear of speaking in front of others.
First, try to learn common phrases and idioms. Knowing these will help you understand spoken English much better.
Use pronunciation and vocabulary apps to make your learning more enjoyable, and practice those for a week to retain them faster.
Find a friend who has a better understanding of the language. Join English-speaking groups to gain more fluency.