I think the moment you begin building, start talking about it, for example in X spaces, linkedin or on insta reels if you can make content. That's how i got users in my first project. It will also give you firsthand idea what features you need to build.

If you describe your MVP using the following pattern:

[customer profile] has [problem] so I built [solution]

Then you should have an idea of who the product is for and then you can figure out where to find them. For example:

Boat owners who store their boats at home don't have a convenient way to move their trailers around so I built a motorized trailer puller that is controllable using a smartphone so they can move their boats without using their vehicle.

So I need to reach people who have boats on trailers. They are easy to find down at any boat ramp or marina. I could go down there and set up a prototype and show them how it works, get feedback, and maybe show them a QR code to join a mailing list. I could also go to boat shows, FB groups, subreddits, YouTube, etc.

Do you have a customer profile you could share, and maybe people can offer suggestions for how to reach them?

Who did you talk to to validate the product design when developing your MVP? They are your first users.

Write about it. Add a blog to your function once you have identified your target audience. Make sure you can create links from the posts. Once you have the short articles, post the link with commentary to where the right audience is. This is often in places like Reddit. Reddit has a lot of topical forums.

You want to sit down and write something called an ICP, Ideal Customer Profile who you imagine would be the ideal customer for your product. This is the primary target.

Then you want to do another thing. Figure out how what you created is being used. It might not be anything which you planned. Once you figure out how your thing is being used figure out where the people who are using it are. Then go there.

Feature someone else's MVP. You scratch my back, I'll scratch yours. It's all one big circle jerk.