If you have cash, index funds might be the highest safest way to invest “An index fund is a portfolio of stocks or bonds designed to mimic the composition and performance of a financial market index. Index funds have lower expenses and fees than actively managed funds. Index funds follow a passive investment strategy.” Last time I heard 8% return annually.
If you have cryptos like Ethereum, then run Ethereum staking, last time I heard it’s up to 11% but could be smaller but maybe average to 6%. You can stop if you need money, withdraw and cash out.
Buy big cap company stocks and hold on for a year or so. With stock you can withdraw money as needed.
Buy a condo or row house apartment whatever in a good area like downtown area and the price will rise.