Well about mining, I'm no expert but this is what i know about it,
You dont just mine for the fun of it, you mine because you'd like to acquire passive income right?, There are some cryptocurrencies that allow or enables user mind with their mobile phones,
If you want to mine and make money off it, you need to first do your research about the coin and check if its profitable or not,
Although there are some cryptocurrencies with which you can mine without having to join any mining farm, but for better profit its advisable you do so,
You can decide to set up a mining rig yourself but it will cost you in terms of electricity except if electricity is cheap in your area
Talking about profitable coins for mining, Veil cryptocurrency can be mined giving you passive income, and it can also be staked (which i prefer to mining), staking veil is very lucrative and all you need is to set up ur wallet and follow the guidelines on the github page, wouldn't cost you much electricity unlike mining which does