...I am trying to learn objective-c coding
Try starting here:
https://www.bignerdranch.com/index
Specifically here:
https://www.bignerdranch.com/books
Purchase and read:
1) Objective-C Programming: The Big Nerd Ranch Guide
2) iOS Programming: The Big Nerd Ranch Guide (3rd Edition)
This will get you off in the right direction, seriously. Anything else you purchase will probably frustrate you or sit on your shelf until you finally give up or get around to these books. Most books are created for classroom teaching where a genius type coding instructor fills in the little gaps that new programmers can get completely lost in. If you are learning on your own, you need a book that caters towards that. After you have developed a little base knowledge, then you can dive into whatever book you are interested in. You will know enough to decide if the book is useful or just crap; teaching the same old theory junk starting you off on completely useless exercises and wasting twenty pages on what an int is.
Good luck
PS I disagree with typical theory based learning. The nerd guys have pretty much figured out how to teach people to code. They teach what you need, when you need it and why. Start with the two above books, in either order, if you start with the second book, because you want to 'jump right in' and start to find yourself lost, go back to the first book until you catch up. There are many things in programming that will completely mess with your mind. Just think about for a second. How long would it take you to learn Chinese? After a couple of weeks, you'd be good enough to struggle through and order a meal and place to stay, but to hire a bunch of people to build a unique structure, like an airplane? That will take years of language understanding, not to mention probably increasing your skills in fluid dynamics, physics, math, ect.