How to Import a custom CSV file into Quicken

Hi - I have a custom CSV file - a gigantic file with all transactions from multiple banks and brokerages. The number of transactions number a few thousands - so I cannot enter them manually in quicken. I wanted to see is there a format I could load the file into Quicken with.

The transactions are of the following nature: Buy (sell) a stock; Buy (sell) a bond; Buy (sell) a CD; Buy (sell) an option; Option Assigned; Option Expired; Direct Deposit; Spend; Dividend (Interest) Payment; Tax and Fees etc. With each transaction, I have the relevant information that's needed (e.g. quantity/symbol etc. for a stock purchase), and the information is blank if it's not relevant.

Is there a way I could import these transactions into quicken? Any specific format I should be structuring the csv file?