What to read before learning Objective-C?

Question

Objective-C

Hello. Actually, I decided to retrain, because. I am very interested in mobile development.
I ordered a macbook, but it will arrive only at the end of November, so it will not be possible to deploy a workspace under Objective-C yet.
Tell me please. What can be read / studied before Objective-C, perhaps some books on OOP or something else?
I will be grateful for the answers.

Answer 1

"Object Oriented Thinking" by Matt Weisfeld,
You can check out C for now (K&R). Come in handy.