I launched an MVP (a community for sharing healthy lifestyle goals). How do I collect user feedback to identify which assumptions are wrong?

I know that the only way to test my assumptions is to put this MVP in front of real users as quickly as possible and reiterate, but how I do actually do that?

Here is my MVP:
µ goals.

And this is why I built it:
Establishing personal goals is important, it helps you stay focused and on track for optimum wellness. We all want to live a healthy lifestyle, but big goals like this can be hard to stick to. Sometimes you get distracted, you let your lazy mind overtake your willpower, or you procrastinate, all of this can make you feel unmotivated and your goal seems as far out of reach as ever.

I built a web app to help people set time-bound, micro goals, that are attainable in a short period of time. People can share their goals with others, so you will have different people working on the same micro goal. By doing so, we can remind each other about the importance of well being, this may bring some motivation, and even better, inspiration.
Achieving micro goals will allow you to get that sense of immediate gratification and hopefully, you can push through it and reach your ultimate goal to get better wellness as you age.

Any feedback would be greatly appreciated!
Thank you.