Dunno about a tutorial here, but if you want to just try it a bit, I'd go with simply downloading AUTOMATIC11111 and go from there.
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You can get a ton of models on civitai - including NSFW on Civitai Red:
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The base models are "checkpoints" - I'd recommend something based on SDXL or Pony for starters and NSFW since it had quite a large community support for uncensored variants, LoRAs (essentially model-AddOns for specific purposes) and so on. But there are tradeoffs for any choice so just try things out and mess around.
Once you're into things a bit deeper you might want to go with ComfyUI. Quite a lot more complex to get things going with setting up workflows and so on but gives more power to customize your generation pipelines in return.
All of those things are very popular and have tons of community resources, so a simple search is likely to answer your questions and more. Welcome to the img gen rabbit hole.