For me, in my 40s and based in Australia, I am invested in Apple and a three different ETFs.

There are plenty of investment forums and subreddits that discuss investment and FIRE strategies, and it depends on your country.

It's never too late to begin.

Generally an ETF or similar is worth looking into :-)

Vanguard. Like VOO or VTWO - and once you have good savings in there, branch out to more divided payers if you'd like them to kick out some spending money. A 4-5% ARR is probable.

This would assume they are capitalized such that 4-5% ARR returns a living wage after capital gains. Most people don't reach this until their mid-50s or early 60s if they're lucky. Sometimes never.

This being the internet, the answer is going to be something useless like Gamestop.

$GME and $AMC and other memes are gambling, treat them as such. That volatility is playing with fire.

I don't understand what the age is supposed to suggest here. Are you asking what to buy and hold until you retire?