As what I have read and searched:
Investing is a way to potentially increase the amount of money you have. The goal is to buy financial products, also called investments, and hopefully sell them at a higher price than what you initially paid. .
Investing is the process of buying assets that increase in value over time and provide returns in the form of income payments or capital gains.
While;
Staking is the process of actively participating in transaction validation (similar to mining) on a proof-of-stake (PoS) blockchain. On these blockchains, anyone with a minimum-required balance of a specific cryptocurrency can validate transactions and earn Staking rewards.
Staking involves holding funds in a cryptocurrency wallet to support the security and operations of a blockchain network. Simply put, staking is the act of locking cryptocurrencies to receive rewards. In most cases, you'll be able to stake your coins directly from your crypto wallet, such as Trust Wallet.
At the end, both are profitable but it depends on your capital. Staking just provide small yearly interest like in a traditional banks but investing give much higher percentage of profit in just a short period of time but it depends on how much, what or where did you invest. You can also choose both if you want to earn more. Everything is up to you, if what you prefer to do to earn.
I think staking is better than investing. By staking a token you will get rewards in that token which means it will increase your portfolio slowly. Also staking is also a kind of investment because you need to buy those assets before you stake it in any place. So by staking you can invest in any project for the long term and at the same time, you can increase that token only by holding it. Whcih one is more profitable?