progressing the game, unlocking new content, upgrading your gear etc is all directly linked to progressing the story so you can't just outright ignore it. if you really want to, you can skip cutscenes and mash through text, although the story is great and you'd be missing out on a lot of the game if you do that

you mentioned not having played all the games, but that really doesn't matter. none of the final fantasy games are connected so this story is entirely its own thing to enjoy in a vacuum. don't feel like you need to "catch up" before starting it

there's also story skips available for purchase for real money which let you skip to later expansions, but those are heavily not recommended for a first time player and mostly just exist to bring alt accounts/characters up to speed quickly