Hi,
For materials that you do not know where to go, put them in your Client Information. That works for both sds and non sds application.
You can only upload one pdf for each slot, and each of them can not be bigger than 4 MB. So try to combine them in a logical order and make a table of contents in the very beginning, if the document contains a lot of things.
If the document is too big, you can use online website (e.g. ilovepdf, smallpdf) to compress it.
If your parents will be your sponsor, I strongly recommend a document proving your relationship with them, such as a birth certificate. Also, provide materials of your parents to show their financial ability: bank statement, citification of property and vehicles, deposit certificate, etc.
If your bank statement is not good, just don't put it in your financial proof.
Conditional offer can be used to apply for a study permit. If you have doubts, you can combine your offer letter and the communication emails together when you upload the materials.
Wish you good luck from China