In cloud mining are you relying on a third party?
Yes, you have to rely on third party and I don't advice you to leap into cloud mining because every cloud mining of this days end up scamming people off their money and it will be better if you invest your money into ICO rather than cloud mining.
Bitcoin mining requires a computer and a special program.Miners will use this program and a lot of computer resources to compete with other miners in solving complicated mathematical problems.About every ten minutes,they will try to solve a block that has the latest transaction data in it,using cryptographic hash functions.