Under their "StayHomeIndiaWithBooks" initiative, the NBT has offered over 100 books for free PDF download from their official website. These books are in multiple languages including Telugu and English, covering a wide range of topics from stories to language learning.
What is your current (beginner, intermediate)?
English is a sound-based language. You cannot learn to speak by reading a pirated PDF alone. You need audio and speaking practice.
Often, educational blogs or forums dedicated to competitive exams or language learning, such as Wiki RSchoolToday , host these files.