The Ocarina is one of the required items for Link to beat the game. Typically, the Ocarina has 3 uses.
Luckily, all of these can be skipped using a variety of tricks.
Typically, you need to revive the rooster and use it to cross the large pit blocking access to the Bird Key. However, it is possible to skip this by either doing a series of Hookshot Jumps across the gap or by doing a series of Superjumps. Hookshot Jump method
Both of these can be skipped by using a Bomb Trigger.