A quick question?!
is it better to invest a lot in one coin such as bitcoin for example. or invest a little in lots of different coins?
Well everything I have learnt in my finance courses is diversify, so I think you should stick to that. Invest in multiple coins, however, this doesnt mean throw you money at coins. One thing you will see in the Crypto space is "signal groups". These groups focus on daily tips, which is impossible to win. The best rule in my opinion for investment is limit your trades. Meaning only buy and sell 4-6 times a month, total. These trades should be something you are sure about, and not just a quick educational guess.