In my opinion, the TAX RATE and ITEM TAX RATE columns don't need to be used, especially for the TOTAL column .... it's better not to use them. It is better if the tax rate is set from the beginning on the options. For the success of importing CSV, don't use the DATE column, because every time I use the DATE column, be it DD-MM-YYYY or YYYY-MM-DD format, import always fails.
Importable data that is sufficient for quoting is as follows:
Quote Code, Customer (Required), Sales Person, Billing Address, Ship Address, Qty, Item, Description (Required), Unit Value, Discount, Comment, Private Comment