Tax management at 18 years old

hello,
I am 18 year old & persuing my BTech CSE, also I earn more than 200k per month by my side hustle which I am now thinking to turn into full time. So as I am 18 I have no idea about investment & taxes, how to manage them, how much can I have for my enjoyment per month, how to invest, where to invest so basically I want a little assistance if anyone can help me with this.

thanks
you can mention your ph no. so that I can contact you.