Some of the mistakes I made I should have probably know before hand is making the Art before the first systems/mechanics.
But to go in order, there are some things I recommend, learn from my mistakes.
Planning: Even if it's just a .txt file. Pour everything you want your game to be in a GDD (Game design document). It doesn't have to be too detailed. But basic stuff like what the game is going to be about, The genre, etc. Should be there. Also, if your game is long to develop, try to keep track of the different things you are doing, about to do in a 'to do list'.
Developing-phase 1: In the desired engine, Create the systems/mechanics your game is going to have, you don't need to create sprites or any specific stuff now, you can use coloured circles and squares. The idea here is to make sure the different ideas you though are actually doable. Don't be afraid or feel bad if you have to change or discard many system/mechanics/ideas for any reason. All games went through that (even AAA). Did you know about the dev rooms in games like TLoU or Sonic? Those are make here. Also, if you are a solo dev, or part of a small team, keep things small. Do not try to create an epic CoD, an MMO, or the next GTA. Or in your case you mention RPG maker, a... idk 'The Witcher'.
-----Small note: If it's your first time with that or a new engine.Don't start with your game right away. Perhaps it's better to first create a small and more or less simple 'ugly' game, no to publish, but for you to practice and learn how the engine work. Also, test stuff, test your game like if your life depends of it (okay not so drastic) but try to 'break' your game while testing it, like, idk, see what happens if you smash a important button fast, what happens if you make your character to go the other direction, try to open a door that you know should be close, things like that.
Developing-phase 2: Once you have your game (or at least many scenes) pretty much created with grayboxes, placeholders simple 'beta' feel, etc. It's time to decorate it. Polishing sprites, creating new ones, loading the right music for the scene, etc, etc.
I think pixel art is still pretty good. All depends of what aesthetic and 'feelings' you want to transmit. Games are Art, and Art is a entertainment medium where a creator transmit sensations and feelings towards an spectator.
Of course, many things will be different depending the engine and genre you wanna make, but I think this wall of text pretty much summarise the overall process.
Also, it's okay if you don't get many or any players at first, specially if you don't promote your game in forums/socials. That or the fact my games are kinda shitty haha, so, perhaps you wanna take all I said with a grain of salt.
Lucks.