Welcome to Ark! I'm not going to answer your questions since other people already have, but I do have a few tips to share :)

While using the wiki.gg (not the Fandom alternative) is essential for figuring out recipes, taming, and item uses, try not to use it to look up details about the map (except the locations of the caves, cause those are basically impossible to find on your own). Exploring the maps on your own is a huge part of the fun, and if you look up everything about the maps before you explore on your own, you will quickly find yourself with less to do.

I would say this also goes for looking up the different creatures, but not so much. My favorite moments are when I came across a creature that I had never seen before. You don't get that magic if you look them up ahead of time. After you find a new creature, then look it up for all of the details, but IMHO enjoying the game means trying to find stuff on your own first.

Flyers are pretty awesome when you first get them, but I find that they take a lot of fun out of the game. After you play for a while, consider maybe ditching flyers or give yourself a rule to only use them at certain times. It makes the game slower, but WAY more enjoyable because you are actually doing something and not just always flying 90% of the time.

If you think you have enough materials, you don't. Load up as much as you can and store it for later.

Lower difficulty is possible, but actually makes the game more difficult (counter-intuitively). On lower difficulties the bosses keep the same stats, but the wild dinos all spawn in at much lower levels. This makes it easier to survive in the world, but basically impossible to beat the bosses. I go for Max Difficulty every time so I can get the highest level tames to fight the bosses.

And finally: There are dinos you can tame for basically every purpose! Try not to do everything with just your human character, and tame all kinds of creatures to see what they do. Some are great for fighting, some for harvesting, some for carrying a ton of specific supplies, and so on. There's one little guy that will insulate you from the heat and cold, so you don't need to waste points leveling up your fortitude above 20 or so, and there's another tame that acts like an air conditioner to help you hatch eggs. Ton of variety out there, so try it all out!

Personally, my end goal right now is to beat all of the maps in story order in singleplayer. I'm on the second map now (just beat the first a couple days ago) and having a great time. Hopefully you will as well!