Good knowledge of Forex trading will really help in trading crypto currency as both are almost similar. Buy and hold for a long time is not some time advisable ( though all depends your point of entry) because there some stock and crypto currency you will hold for a longer period and it will become worthless or become less in value as compared to when you bought them.
I also trade forex, it is most times helpful if you are a forex trader before coming into cryptocurrency trading, it'll aid you to get acquainted in taking risks and understanding how to trade without emotions
Long time trading is good for the bitcoin, it cannot become worthless or lose much value to make it that, but hodling ico coins or alts for so long is not advisable if you ask me, it always has the potential to crash.