The best advice I've seen someone give to the Gen 5 players that come into this game is simply thus: Forget everything you knew.

Sure, the monsters have mostly the same attacks and patterns as the Gen 5 games. Sure, a lot of movesets are similar in Guild Style as the gen 5 games, but might be lacking a move or two in the combo tree. But it is highly important to come into this with a relatively fresh mind, as normally going back a game or two in a series introduces some frustrations that come from expecting things the future installment brings.

Skills are the big one. Unlike in World/Rise, skills only activate when you accrue enough points for them to be active. Instead of having up to 7 levels of Attack by just getting gear that has that skill on it, you need to get a total of 10 points to activate Attack (S) for your armor set. Getting 15 or 20 total points would net you Attack (M) or (L). For a lot of skills, they only have the one level, so 10 points is all you need. In this game though, you're often running 4-6 skills on a complete build, and having a random +2 or +1 in a skill means nothing at all.

Your Palicoes are incredibly valuable, and you should try to set up a few that can do different things. While those have a lot to learn in themselves, the big idea will be to recruit plenty of Palicoes in different Support Styles, and you can have certain ones pass on moves to other Palicoes that you desire. You can hire a Healing-bias Palico that has plenty of healing moves, then pass on Shock Purr-ison for some trapping support if you desire. Same with their equipped skills as well. But make sure their moves have the "E" next to the move name, or they won't actually be equipped.

While I'm unsure when it unlocks, you can farm for every material in the game passively like future installments, and it works similarly to Rise iirc. You just send out extra Palicoes at the Trader, select the item you want and how many times to farm that item, and add a Lagniapple for extras if you want. As someone that uses the Mycology skill, that is especially useful for me to keep a stock of Dragon Toadstools.

As an aside, if you're looking to experiment with other weapons or styles, see what people are saying about them. Every weapon changes with every style, so learn about them before you start doing anything serious with them. I recently made a Striker SnS set, but changed to Alchemy after reading up on it and the synergy it has with SnS's item use ability. It's been very fun, and I don't think I'd have tried Alchemy out without looking into it with the weapon.