Need help from my fellow Singaporeans

[251b1352]

Hellooo, I am very new to freelancing and I am quite worried about tax stuffs because it's my first time handling these. I am getting my first pay soon, and would like to know what or where do I have to declare everything to the gov. I know we need to declare self-employed for sure, but how do we prove our salary and what not? My current payment settings for Upwork is that the money will be transferred directly to my DBS savings account every week. Do I need to show my bank statement every month as proof? Also, what about CPF? I think I read somewhere we need to topup our CPF by ourselves for self-employed. Please help a very lost sheep hereee. 🙃