This is purely just to help some people who are struggling with fish locations, I have sectioned the guide to make things easier for newbies.
All references I got were off of the official webfishing fandom.com website.

Please do not spread any hate about the creator of the game, thankyou
And if possible please show some love I would really appreciate it..

Freshwater fish can be found in the ponds located on the main island, as circled:
















With no weather events, you can catch these fish:

• Bass
  
• Bluegill
  
• Catfish
  
• Crayfish
  
• Drum
  
• Frog
  
• Goldfish
  
• Guppy
  
• Koi
  
• Perch
  
• Rainbow Trout
  
• Salmon
  
• Snail
  
• Sturgeon
  
• Walleye

• Bowfin
  
• Carp
  
• Crab
  
• Crappie
  
• Leech
  
• Muskellunge
  
• Pike
  
• Toad
  
• Turtle

• Alligator
  
• Axolotl
  
• Bullshark
  
• Gar
  
• Golden Bass
  
• King Salmon
  
• Mooneye
  
• Pupfish

Depending on what fish you are looking for varies in the pond you are fishing in, personally I find finding alligators more easier/common in the main river, running through the middle of the map near the spawn area.

Using common knowledge you can guess that you will find saltwater fish in every area which is not a pond or a river. To put it into basics, the ocean. Here you can find much bigger fish depending on what bait you are using.

With no weather events, you can catch these fish:

• Angelfish
  
• Atlantic Salmon
  
• Bluefish
  
• Clownfish
  
• Dogfish
  
• Eel
  
• Flounder
  
• Grouper
  
• Herring
  
• Krill
  
• Lobster
  
• Oyster
  
• Sawfish
  
• Shrimp
  
• Sunfish
  
• Tuna

• Hammerhead Shark
  
• Lionfish
  
• Marlin
  
• Octopus
  
• Seahorse
  
• Stingray
  
• Swordfish
  
• Wolffish

The big guys..

• Coelacanth
  
• (GOLDEN) Manta Ray and Manta Ray
  
• Great White Shark
  
• Man O' War
  
• Sea Turtle
  
• Squid
  
• Whale

As of now, there is only one main weather event, but there is also a meteor shower, which I will get into more detail about further down this section.

RAIN

The main weather event people focus on more/is more important is rain, it is typically an easy event to spot and starts randomly. But if you look up and see a huge storm cloud, go for it! Because you'll have the chance to catch 4 fish that are usually unobtainable when there is no rain.
These fish can be caught anywhere

• Anomalocaris
  
• Horseshoe Crab

• Helicoprion

• Leedsichthys

Oh how I aspire to be able to catch this fish bro.



This event is usually overlooked, is it only really gives you one fish each time. But personally is my favourite. Every now and then, randomly, a single meteor will fall from the sky, you will hear it, and if not, "What was that...?" will send in the server chat in green text. It will have fallen somewhere upon the main map and can be spotted easily from the smoke above it.


Once finding it, if you cast your rod onto it you will be able to obtain "Unidentified Fish Object (Tier 2)"

The void is an area in webfishing which many find difficult to get to. Along with notifying you guys on what fish you can catch, I will also elaborate on how to get there. Thank me later.

Go inside of the fishing store, where you would usually get your clothes or rod upgrades from. Walk to one of the walls and drop a private island prop just the other side of it. Enter your private island and immediately leave it. Then you will spawn back outside of the fishing store.
You can fish there as usual. If you need to exit just run in one direction and eventually you will drop off and respawn at the usual spawn area.

There is actually only one fish that is exclusive to this area.
"CREATURE" - (TIER 2) is a fish that can be obtained in the void. Its quite peculiar.