What is the current end-game?
The official page points at apex status in The Deep. No later badge or size cap has been published.
Advanced
Stay the hunter. Size, traits, and biome choice beat copied tier lists.
Updated

Servers hold 60 players. The official page tells you to fight them. Advanced play is not a solo PvE route — it is deciding when you are food. If a larger body enters your reef pile, leave. Deaths still pay +300 in footage, but they also donate your body to someone else's growth.

Healing 95% is the documented panic button. Bite Speed 5% is the documented farm button. Reflex / Quick is labelled but unnumbered. Pick the bottleneck you felt in the last two deaths, not a YouTube animal ranking from another game.
Official copy uses if you dare and CAN YOU SURVIVE. Treat The Deep as a place you enter to convert size into apex status, not a place you enter to find size. If you still need the Fish Tree tutorial, you are not ready.

This title is tagged like Feed and Grow Fish on purpose. It is still a different Roblox experience with its own Fish Tree, trait panel, and two-badge start. Copied megalodon routes from other games are watch items, not facts.
FAQ
The official page points at apex status in The Deep. No later badge or size cap has been published.
The official description includes fighting other players. You can try to avoid them, but 60-player servers make that a temporary plan.