Its not advisable to invest all in Bitcoin there are other good investments that are also worth investing in the likes of Gold and others... Bitcoin has its glorious moment and it's crashing moments it's never always Rosy so invest a certain percentage in Bitcoin an amount you can lose without having a major effect
When people will invest in bitcoin they have to do some deep research first about crypto. It not safe investment indeed they have to understand how this works. As have been known crypto is volatile although it is good investment but cannot guaranteed the market price may plummets. So before they will invest they should understand the facts in bitcoin.