"How do I acquire users" is the entire function of sales and marketing. A single HN comment explaining how to do sales and marketing, which is highly dependent on your product and market (and much more difficult than technical people tend to believe), is a bit unrealistic. And a great opportunity to use Claude/ChatGPT for something other than code. There's no silver bullet but as a springboard you can think about:

Who is your ideal customer profile (look up buyer personas) -- if you're B2B figure out both the profile of the company who would buy, as well as the person who would actually buy, and the person who would actually use the software: remember that buyer != user in B2B scenarios, and you'll have to figure out if the buyer, user or both is the best path to getting a sale. If you're B2C figure out your buyer personas so you know where to advertise.

Why would people want your product; sounds like you may already have this down but be ready to explain your value proposition concisely.

How will these people hear about your product -- a SaaS that falls in the woods doesn't make a sound, you need people to learn your product exists before they can pay for it. This is the point of figuring out buyer personas, you need to meet your customers where they are, and you can't know where they are unless you know who they are. This is highly dependent on your product/personas, and could range from running LinkedIn ads to SEO to having a Bluesky brand account to going to local meetup groups or conferences and trying to get your first handful of users in-person.