Question about Indexes and ETFs…

Ok, so I have a question. Since ETFs like TQQQ/SQQQ, and the SPY are based off of indexes, does price and volume of shares traded in the ETF itself actually affect the price action…or, is the price action you see on their charts based on the cumulative price action of every stock in its index??

It just seems like watching a ton of volume go into TQQQ shouldn’t really affect the price, if it’s following the QQQ, which is following NASDAQ.

Sorry if this seems like a dumb question: I’ve been curious about this for a while.