Security question related to DeFI

Hey guys, I'm pretty scared of signing malicious smart contracts etc because I've heard a lot of scary stories. By now I only use a hot metamask wallet to interact with defi, and my question is if I could connect my ledger to metamask and choose a new account where I don't have any funds to HODL on and use only that new adress for Defi? As far as I know in the worst case, if I sign a malicious SC, only the funds of that account would be lost and not all my hodl funds on other ledger accounts? Is that right, or would you suggest to not use my ledger at all for Defi? Thank you so much. I'd like to know what would be the smartest choice, I think that if only the funds of this account could be lost in worst case (and not my other hodl ledger accounts) it should be better to use the ledger and revoke smart contracts after a time.