I'll start with what you already know: Index funds, with portfolios determined by computer algorithms to reflect categories of stocks and bonds, have a much better track record than funds whose stocks and bonds are selected by human beings — so-called actively managed funds.
Over the 10 years ending December 31, 2025, research firm Morningstar calculates, only 3.6% of active large-capitalization growth funds have beaten the average index fund in the same category.