If you speak English, I suggest watching the linked video.

But in short:

You combine many little UTXOs (those might have gathered on your hardware wallet via DCA plans - each transaction creates a UTXO) to one bigger UTXO by simply creating a transaction considering of those tiny UTXOs to another Bitcoin address that you control. If the transaction fees keep rising in the future and you want to surrender your bitcoin one day, you're going to save transaction fees by merging your UTXOs when the fee market is calm - which is now.

Some hardware wallets offer you an option called "coin control" or "UTXO management" where you can select which UTXOs you want to include in your transaction.

https://www.youtube.com/watch?v=33H3uqgmw6k