getting my product online

Hi, I have been working on an online program that I am almost ready to launch. I am very excited about it, but the logistics hold me up. I have a technical question. I have a SQUARE SPACE site. I am currently using MailChimp for my email list, which I will soon need to upgrade. I have set up a commerce page on my site for my other business, local food delivery service. I have an ebook available for sale, but the delivery is not ideal from the Square space commerce. I am looking at using Ontraport, but they integrate with WordPress. I have worked so hard on my website, I hate to switch and start all over. But if I am moving my business to online content, I have to figure it out. What does SCS use and what do you recommend?

I am really excited to be at this point, but I procrastinate the final steps because they are hard for me and I am also scared my online product isn’t going to sell. I am working through those thoughts. It’s taken me a long time to get to this place, I am ready to fail! I know I’m ready to get it out there. Thank you!