Help needed: Open source react component

Hi fellow DEVs 👋,
A while ago, I created a basic react component, a wrapper for some multi step flows. This was my first ever react component that I wrote in an effort to learn and understand react better.

TL;DR

I want need some help with the functionality where user is allowed to call some custom method/actions (synchronous or asynchronous) before proceeding to the next step, and go to next step/show error based on the user method response.

What is the component about?

It is a dynamic, multi-step progress indicator with navigation buttons to move between steps. Optionally you could have some basic validation when proceeding to the next step.
It has nice little animations and ZERO dependencies (till now).
Excited? Go check it out

What I need help with?

I wanted to allow people to call their own custom methods, either synchronous or asynchronous, before proceeding to the next step. Right now, I have an optional prop to allow for custom validation to be performed, but that is very naive as the validation function must have a return type of boolean, and no error message is shown.
Ideally, I would like someone to help me achieve this but if you'd like to raise a PR that's fine too 😄, I can't seem to plan the whole thing very well

How to get started?

I already have an issue in the Github repo.
Hit me up in the DEV chat or Discord(username: saini-g#3132) if you want.

How else can I help?

Any suggestions, PRs, ideas, help with documentation would also be nice.

Thanks.