Red Dead Redemption 2

This will be the first achievement you get.

Easy enough to get; stay on the same horse, feed it, and pat it while riding with L3 (press in on left stick). Bonding level will increase to level 4 (the max) soon enough. There's time to do this 3 times over on a good playthrough of the game.

Do this before completing chapter 4 - as the tithing box is not available after chapter 4.

It takes about 45m to get started in online, you have to go through this to get to free roam.

Loot every dead body, this should unlock before you complete the story.

Easy to do from near the beginning of the game in any gunsmith. Just upgrade everything on a pistol or revolver.

Easiest during Ch4 after you unlock Special lures.

You can't really get this until during/after chapter 5 - because honor is capped until then. Stay positive Honor, so you can be eligible for all the missions needed for Lending a Hand

You must do a companion mission in chapters 2, 3 and 4. They appear as small white mission icons as you progress through each chapter and are to go do things like fishing/robberies/etc with the minor characters.

You should be able to do this in Ch3/Ch4 - just craft one of everything you can. Obviously make sure to buy & pick up (and read, from your satchel) any/all recipes you find.

You only need to start a game of each. You don't need to win.

Easy to do from the intro onwards in the obvious way... ...just use Eagle Eye to spot pickable things and pick them...

There are way more than 10 in the game. You must complete the full quest line for each - not just the first mission. You can still do any/all of these after completing the story.

You must do this before the end of chapter 4.

This character gives a set of stranger missions in Ch4, from Saint Denis. They'll be in/around a small building right at the north end of the map. Once the mission chain is complete, return to his building after 24 hours or so to learn the fate, get the achievement, and also a reward item.

This can only be done *after* completing the story, although you can visit some of the graves during the story from Ch4 onwards. See rdr2map.com for locations.

Best to leave this until after Extreme Personality and Lending a Hand - you'll need to rack up a large bounty in each state, and then camp out in the wild and sleep a lot to have the time pass.

This can only be done after completing the story.

There are 178 species. That is a lot. Keep track in the pause menu under Progress -> Compendium -> Animals

See also Skin Deep. Use the binoculars. Check in the compendium for 100% progress against each animal.

You have to let the bear attach/maul you first, then fight it off and kill it. A pump action shotgun is pretty handy here, assuming you don't care about pelt quality.

This is definitely easiest to do when you first attempt each mission - if you replay them you don't have your normal collection of tonics/weapons/etc. Ofc the game doesn't reveal the requirements for Gold until after you've completed at least once - but 3rd party mission guides will help with that.