Fixed investment + buy at the time of pullback

The rated investment index SP500 is fixed every month, and the expected annual return is 7 to 9%.
Every 5% correction, buy the QQQ and SP500 indices, then sell at a high level to create a swing.
Of course, they will also buy favorite stocks, such as TSLA, AAPL, GOOG, MSFT, LULU, MA, U, etc.