How to validate if people will use my product?

I am a tech guy at heart and I am trying to build something that will make me money and people will want to use. I have built the first version and people are signing up but will they pay I'm not sure.

So now I am trying to reach out to people on LinkedIn and other places. They are mostly people who might be using a similar product in the field of marketing. Also, the product I am building is not something very innovative it has a quite some competition but I think the market is big enough and I can get a share.

My end goal is to understand if people have existing challenges so that I can tailor the product to solve those pain point and get some USP out of it. I'm sure people have cracked this before. Will you please give me some tips?