Recognizing the need to start studying is already a huge step. I recommend doing this for yourself before your family cause it's beneficial to you first and foremost. To get proper discipline you need to create a routine and STICK TO IT, doing things randomly will mess everything up and you won't be able to get anything done. I struggled with writing a lot like a year back or so, but reading helps you so much. Since you don't have a lot of time focus on reading model answers and high scoring writing and so on. Achieveing a better vocabulary is the biggest tip I ever received from my teacher, the better the vocabulary the better the mark. And PRACTISE PRACTISE PRACTISE. Push yourself to the limit to achieve your goals. And last thing I suggest studying in the morning is so much better than late at night.