Do a little research, there are many people out there that started mining and then decided to give up quick and want to get some cash out of the equipment. Put as much thought into the storage and care of the units as you do the units themselves. Keeping them cool and running well is a key to success.
Instead you asked him to research about it you can send the reference which can help him or you simply no need to post this without any information bro.
Youtube is the source to learn mining or trading. There are many articles available to learn what is bitcoin mining upto professional level.
ASIC miners are good to mine bitcoin and GPU is good altcoin mining.