deposit to core account vs re-invest in security

I currently have some money in VOO and QQQI

I just checked and they are both set to "deposit to core account"

The VOO is the long term investment and the QQQI I want to take dividends out

This is probably a stupid question. But for this purpose I would update VOO to "reinvest in security" and QQQI leave at "deposit to core account," correct?

Also...when depositing to core account where does that go? Does it sit in the cash available or does it go to the Fidelity MM?