A fuse will not stop the ESC from dying, but it should prevent it from destroying your boat. If a car type fuse holder is fitted, you can use a box of assorted fuses from the Pound shop to determine a value that works, and your current draw will be a bit less than that.
Since reverse still works, it's likely that it is one of the reverse transistors that has gone short circuit, or stuck switched on. When you try forward, that puts a dead short on the power, and releases the magic smoke.
Points to bear in mind with oriental ESCs -
1 their amps are a lot smaller than ours, allowing them to put bigger numbers on the box
2 an amazingly small ESC, to carry a large current, must have truly wonderful semiconductors to not run very hot
3 since they are going to run very hot, and they don't have much surface area, they need to be in a tremendous cooling airflow
4 quality control is probably an optional extra
5 sales and marketing people are generally incurable optimists. This is not a good thing where technical accuracy is wanted when combined with their traditional ignorance of what they are selling and marketing.