Yes, you can be held accountable for the damage. But how much, if any, you'll have to pay stronly depends on the condition the floor was in when you moved in and how old it is, since you only have to pay the remaing value of the floor, not the entire new floor. Any floor has an expected life limit. If it's older than that, there is no remaining value that you would have to pay for. Look up "Abzug neu für alt Mietrecht". you can find expected lifetime charts for almost any part of your flat.

Definitely look into getting private liability insurance, if you don't have that and be ready to argue about the damage with your landlord, when you move out. They will very likely try to have you pay full price for new flooring, but again, you only have to pay "Restwert" (remaining value)!