If I renew my passport, will it nullify my current visa?

Hi there.

More info is needed to answer acurately. Which nationality is your passport, what type of visa do you have.

As an example in UK, if you renew your passport, your visa is still valid, although you have to travel with both the old and new passport.
OR you can pay a fee to get the visa transferred to the new passport. Sometimes this costs a fair amount (e.g. £165 for indefinite visas)

Hope that helps a bit