How to allow users to use an app’s major functionality (without overwhelming them with forms)?

We are building an app for consultancy (online conference). However, before the customer can engage / connect with the consultant, to best serve the customer, there are several questions that the customer needs to answer.

We don't like to overwhelm the customer with questions to answer before they can use the app's main function.

So we are thinking that maybe:

When the customer uses the app for the 1st time, they don't need to fill-out so much information. That is, at least, they can try the app's main functionality and if they like it enough, it would be less of a hassle for them to fill-out more forms (maybe on their 2nd/3rd time using the app).

Do you think this strategy will work?