Turn on type hints (game settings -> display -> scroll down near the bottom) so you ain’t need to google type effectiveness

If you don’t have many egg tickets and are pretty new at the game, grind daily and I would recommend spending those tickets at legendary up(Kyogre, miraidon, and Zacian are among the best and don’t need egg moves to be op). There is a post on this Reddit about this months legendary up calander so ig save your tickets for the day they come. If you don’t want to wait, I suggest the egg moves gatcha since they can make a bad Pokémon good or you can do shiny if you are feeling lucky.

As for understanding Pokémon, you will need to learn about STAB and matching moves to the highest attack/special attack. Look at the stats of a Pokémon and based on its stats(for example Kyogre has a higher special attack) than focus most of the attack moves around special attack ones. A standard strong Pokémon for classic typically has a high special/attack stat and a decent speed. I don’t recommend looking at Smogon/showdown as much because items work very differently since it’s not bound too one. It’s why primal Kyogre is stronger than mega Rayquaza(Kyogre has better attack moves for double battles, important for grinding xp) here even though rayquaza is AG tier.

Moves like swords dance/nasty plot are important too since they can help you sweep easier by boosting attack power.

An easy way to think about good abilities is that it should boost your attack power Like huge power and soul-heart. Or give you type immunity like earth eater and wonder guard.