Make no mistake, quantum computing is a threat towards anything secured by public-private keys. The amount of qubits required to break ECDSA is above a thousand and currently, there isn't any quantum computers that is close to that, without running it for longer periods of time and without errors.
It's not hard to design a new algorithm to secure the signatures but the harder part should be about securing the addresses with coins and were P2PK.
If i may ask what is quantum computing?
And what are the functions of quantum computing?
Which axis of cryptoccurrency can we apply quantum computing.
We are here to comprehend what we don't know the basic idea.