How can I start a brainstorming strategy service to help novice entrepreneurs?

I love talking to beginner entrepreneurs who want to start a new business and listen to their thoughts and brainstorm ideas (a.k.a strategy sessions). I find those early stages thrilling and love the excitement of talking through a new idea with someone who is excited about it, bouncing ideas back and forth, and writing down final thoughts at the end. I like the idea of doing this as a part time consulting "side hustle", but I have no experience. I'm not well spoken, I have some "Ums" when I talk. But I just like listening to people and giving my opinion on things that could help them when I can. I do have a pleasant personality (I think) and am a good listener. However I have no experience in the real world. Can I get started as a "Professional listener" to small business beginners who want someone to listen to their idea and give feedback? I think I can just read books by good authors and repeat some of that knowledge to clients and that would be helpful to them. And join a Toastmasters group to communicate in a more polished way. I would love to offer short 30 minute Skype sessions to people. Any thoughts on how I could get started? My fear is to have clients ask questions that I can't answer, and them feel they wasted their time. I would be perfectly happy starting out for free to gain experience, or offering clients a free 15 minute trial to see if I'm a right fit for them. I love the idea that as years go by I'll get better and better and can seriously increase my income with more experience.