folks have had a generally good experience with it without spending any money
Secret to that is spending gacha rolls that game gives you in a smart way. First thing first - familiarize yourself with how banners work. There are time-limited banners and a constant one. They use slightly different currency for rolling. These currencies are either given as-is from doing stuff, or can be converted from general currency named Primogems, which can be either bought or gained from a variety of activities. It is unadvisable to spend primogems to roll constant banner, since it can possibly give you way too much shit, and you have no way of controlling what you will get. But if you got things that can roll it, then you may jam all with no hesitation, unless they change something. Time-limited ones are where your resources should usually go. But there you should consider what are you rolling, because characters can be very different. Some suck, some very much not suck, etc. As long as we're not talking the end-game content, any character is workable, but I'd still suggest focusing on the good ones at the beginning. Which are good ones wouldn't be easy to detrmine for you. So, I suggest asking in this thread for the time being.
Now, on getting characters. You go to the banners page, which will unlok soon after the beginning, and jam "Wish" button. It can be x1 or x10. Both use up some amount of your currency and prefer a roll on the rarity table either one or 10 times. Before you read some stupid shit on reddit or hear it in youtube shorts, Wishing x10 is exactly the same as Wixhing x1 ten times.
Now, rarities of shit you get: Most desired stuff is referred to as 5-star. Each time you wish, you have approximately 0.6% chance of getting a five-star. 4-stars is the next tier of stuff. Each wish have 5% of giving you one of those. Everything else is 3-stars, it's mostly underwhelming weapons and it's what you mostly get. But since 0.6% is an objectively shit rate, there's a catch. Both five- and four-star items have a so-called guarantee after a certain number of failed attempts at getting one. Every ten wishes will guarantee you at least one 4-star thing, and every 90 wishes will guarantee you a five-star thing. Every time you get a thing, its respective counter for guarantee starts anew. There's, however, another layer of complexity.
Time-limited banners work as such: you have a featured 5-star character and three featured 4-star characters. There's also a weapon banner, but you shouldn't touch it till you know what you are doing, trust me. Every time you get something better than 3-star, game checks what was your last thing of the same rarity. If it was something from the banner, you have a 50/50 chance of getting something from current banner or from standart pool of the respective rarity. If you did not get thing from the banner, next time you get something of that rarity it would be from the banner. And that guarantee persists between the time-limited banners, which is good. So, in order to deterministically get a 5-star, accounting for the bad-case scenario, you'd need 180 rolls. And with 4-stars there's no 100% defined numbers, since there's 3 characters on the banner. Every time you get a four-star from the banner, game flicks a 3-sided coin, a classic asian gamedesing fuck you, to determine which one you get. You can spend A LOT of currency chasing new four-star, so don't get caught in that trap. And don't touch the weapon banner. It requires timely resource commitment to negate it's more scummy system.
Characters fundamentally divide into two groups: 1. the ones that want to stay on the field and do their stuff and 2. the ones that do their stuff with continuous effect and fuck-off. You can have up to four characters in your party, but at every moment you controll only one of them, with the ability to quickly swap between. That's why supports are usually, more valuable for your account. But you need at least a few of those who want to stay on field, since they usually deal most of the damage. Most characters are easy to utilize, but I recommend making a habbit of reading their skills and then trying to understand what they do on practice.
I think that's enough information for now. Download the game, play it for a bit, shank some monsters, loot some chests and determine for yourself if that's to your liking. Genshins systems can be quite wordy, but not actually hard.
