i seem to recall gotchas about ETFs... the in and/or out fees, perhaps...
For what it’s worth, Vanguard mutual funds are noted for their low fees, including the funds mirror different aspects of the market: S&P 500, low cap, mid cap, large cap, world, etc. Mutual funds trade at prices set at the end of the day.
Vanguard also offers ETFs that trade at whatever their value is at the moment, but you buy them through a broker and thus pay the broker’s fee per trade.
If you buy individual stocks, wisdom says you shouldn’t have more than 4% of you portfolio in any given stock. GE was trading at $25 as recently as September, announced a dividend cut/restructuring and now is trading at around $18—painful if all of your eggs were in the GE basket.