I can't decide between Poliwrath, Golduck, or Lapras, I don't want to deal with a magikarp

I’d say lapras, I don’t really know how good it is, but with its ice typing it might be pretty good against dragon types near the end of the game

polywrath

either polywrath or goldduck

Gyarados

I'd say Golduck, I'm pretty sure that it's kinda good with speed and attack, plus I'm pretty sure it can learn Detect or Protect.

Polywarth

I suggest Gyarados, but as another commentor pointed out already, Lapras is also a pretty solid bet.

Polywrath is bulky and hit like truck
Golduck can rip teams to shreds but one thunderbolt and it dies. Your choice

Lapras has a good 130 hp stat and a decent 85 on both attacks, if you haven't given surf to anyone you can give it to Lapras, Surf/Waterfall if you want flinch, Ice Beam, Sing, Perish song, Lapras has a bad movepool, so it's move choices are limited.

Golduck has a decent stat with 95 on Special Attack, going back 1 step to Psyduck, it doesn't learn any useful moves other than Confusion at level 16, so lets go back to Golduck, Golduck's only real water moves are the HMs, it learns Hydro Pump at level 58, that's way too high and i guess that you are in the beginning because you don't want to deal with Magikarp, so Surf/Waterfall if you want flinch, Ice beam(It only learns this through TM), and i can't put in anymore moves here because Golduck only learns 11 moves from level up, so i'd suggest not pick Golduck.

Poliwrath has the secondary Fighting type which could make it a bit more useful, unfortunately because it's a physical attacker, it probably wouldn't make good use of the water type, Going back 2 steps to Poliwag, it learns Hypnosis at level 7 and Double Slap at level 19, so try to get yourself a Poliwag below level 7, also it learns belly drum at level 37 if you want that then delay the evolution a bit, going forward a step to Poliwhirl, it only learns 1 move i would consider useful that is Body Slam at level 35, a really useful move from the move tutors are Mega Kick, Mega Punch, and Seismic Toss, so now, go forward again 1 step and we are back to Poliwrath, it barely learns anymore moves, so the evolution would probably only boost the stats, so probably Seismic Toss, Body Slam, Hypnosis, Double Slap/Surf/Waterfall.

A Really difficult choice, none of them are really that good, but the winner of this i would think it's Lapras.

I just know there is gonna be a reply down here about not reading this

If you didn't understand why i said Poliwrath won't make good use of it's water typing, the physical/special split was in gen 4, Fire Red was gen 3, and water before the split was a special type, which means every water moves are special

the complete opposite here bud

Also Vaporeon is strangely probably the best option other than Gyarados and Lapras, with 130 hp like Lapras, and 110 Special Attack, probably Surf/Waterfall/Hydro Pump, Ice/Aurora Beam, and Acid Armor, and idk Sand Attack? But i must say, use it at your own risk.

Don't say it.

We won't.