I don't want to get sucked into the hype, but I haven't been gaming at all recently and maybe this will give me an excuse to
never tried the other games though
You'll be fine. Witcher 3 is extremely welcoming to new players. CD Projekt RED knows this is the first Witcher game people will play. This is the main reason you always hear them refer to the game as The Witcher Wild Hunt instead of The Witcher 3 Wild Hunt.
First two games aren't necessary. All the story recap which is needed will be done in game.
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