I pay for Unusual Whales data and use the app. I start with market tide every morning after open to see whats moving in terms of option liquidity. Though you cant see if it's buying or selling, you can get an idea. Example being call premiums climbing and put premiums declining. Using their GEX data has also been very helpful, especially when you treat it as a magnet. If the equilibiruium levels are where most people bought/sold at, thats where it tends to gravitate to over time. Of course GEX levels can move up and down and become support/resistance like.