Boat clicks once, does not start?

Hello, thank you all in advance for the help. This is my first boat, and post, so please be patient
The engine is a 1976 Johnson 55hp. We had it in the water and it was running fine. We had been cruising for about 10 minutes before throttling down to neutral and the engine stopped running. We tried to start the engine and it wouldn't start. We took the cover off the engine and checked the fuses, all were OK. The boat restarted after letting it sit and tinkering in the engine with the fuses for about 5 minutes. After starting it, it died again in the water. Loaded up, brought it home, now when you turn the key it clicks. One single click. You can hear the click from the choke as well. I bypassed the solenoid and got the same click from the solenoid. I tried testing the starter by running a positive lead to the starter hot point, you could see spark from contact but the starter did nothing. The boat is in neutral. The battery is new and fully charger. The connections are good. Why won't the engine turn over? Would the starter be a problem with the boat dieing in the water, or are those separate issues? I have not volt metered anything yet. Should I replace the starter? Thank you in advance for your help!

Since you hot wired the starter and it didn't crank the engine over, that indicates that the starter requires re-working or replacing.

The engine stopping while running would be a separate issue most likely.

After you have the electric starter issue solved & corrected.... remove the black/yellow wire (kill circuit) from the powerpack or the ignition switch, whichever is easier. If that cures the shut-down problem, replace the ignition switch.

NOTE that with that wire removed, you will not be able to shut the engine down via the ignition switch.