These audios address everything I think singles should know from first date to building the relationship so they and the children will be safe and build secure attachments.
For now although, my advice is that you use this situation as an opportunity to set a boundary and say no. It’s important that you see how he handles your feelings (additionally his response may expose some potential red-flags).
Tell him, “I really enjoy getting to know you, but feel uncomfortable meeting your kids yet. Let’s keep dating, having fun, and just see where things go in time. If this develops into a relationship then I would love to meet your kids. I would love to get together with you on a different night than Friday or after dinner with your kids. Let me know what you think.”
I hope that helps.