Have you ever started investing around a market crash?

As I venture into investing, I'm diligently conducting research. One source suggests a promising 5+ years ahead, while another predicts a potential collapse starting in 2024. Should the market crash, I wonder if others have begun investing during such downturns. What are some secure companies or sectors suitable for someone new to investing, seeking a cautious approach amidst varying speculations about the market's direction? $SPDR S&P 500 ETF (SPY.US)$