In life many things are unpredictable, for example there is a need for a spur of the moment because we are sick so we have to be thoughtful to divide money, advice I was 50% for saving and 50% for investment.
50% is a lot for investing. because in most cases specially in crypto. the chance of getting lost is very high. so I would prefer using 10% to 25% of my earning to invest back in crypto.
It depends. If you buy the good coins. You will lose very little.