50 days is more than sufficient If you are really eager to read the whole course book. Start with your NCERT book , go through initial chapters and understand the concepts. Don’t skip any concept of you don’t understand it as most of the topics are related or you will find its significance in the later chapters.
Distribute the chapters day wise and try to complete it in time. Don’t rush through the chapters just to finish them. Try understanding the crux of every chapters. For the initial chapter it will take mostly a day or two to finish them. For later ones it will take time. Plan accordingly. If you dnt understand any particular topic look for ur peers and mentors. Google will be of help too.
Believe me 50 day is more than sufficient (“I made it in even less no of days back in my time 😛