When I first started programming, I was in my mid-twenties. I started a lot older than most, but I will say that grasping the basics took me a bit longer than most. I remember when I bought my first programming book, and I read and reread chapters over and over again until the concepts made sense to me. I found that a lot of books talked to me like I had majored in computer science. As you progress through this book, take your time—and, if you need to go back, it is okay to do so. No one is going to care that it took you an extra day to understand a concept. It is more important that you fully understand that concept.
One tip I would give you is to not copy and paste code. No matter where you find the code and no matter how long it takes, it benefits you to type it out. Doing this really helped me as I eventually started to remember the code and it became second nature to me.
In the last chapter, we went over the basics of Swift to get you warmed up. Now, we will...