This question had been answer multiple times in this forum which I think op can go through the chat and get answers to his or her question.

Holding is just like buying a stock and adding it to your portfolio for a long period of time before selling it back to the market. Why staking is a form of holding buy putting the asset into a firm of working or a Liquidity Pool whereby you get returns maybe daily, monthly or annually. The both are risky cause loses can be attracted that is why it's good for one to be more vigilant and knowledgeable of the crypto market.