How does my world enter the fortress from the well?

It is more troublesome for my world to enter the fortress from the well. The water well is deep, and it takes a little time to reach the fortress by digging underground, so players can easily die of lack of oxygen. Here are some ways for Mimi to get into the fort from the well.

Use modifiers. First, use the creative mode to find the well (it was born on the roof, and there was a fortress under the well next to it), then dig down all the time, and then use the modifier to change to the survival mode.

Block up the water with a ladder. Because the well is 2*2 square, when diving, put a ladder by the well and the water under the ladder will disappear. Then put the ladder on the adjacent sides, so that the water on this plane disappears. When digging, come up to breathe oxygen and then dig down to find the fort.