Would you like to have a service where you can get experts answers of your questions?

I would for something particular, for instance car repairs. Else, wouldn't Quora be a go to for something like this?

I'm using Growth mentor from time to time. I would say what matter for your platform to b successful is to focus on a niche. Also do you plan the answer to be open like on Quora or visible only to the one who asked?

When users say thank you for making the website I made

For sure, but will this service provide answers to any kind of questions?