The difference is very big, although someone who invests in the long term, i.e. HODL, can also staking coins.

HODL is just the word "hold" except that letters L and D are swapped. One of Bitcointala users made such a mistake when he was drunk and this form began to be used.
It just means not selling, but holding cryptocurrencies even when there are big price drops in the market.

Staking is simply locking coins for a percentage income. Just like keeping money in a bank deposit for the same purposes.