First time Audi owner, questions

I posted last night that I got my first Audi, but I wanted to get some guidance to make sure I take care of it properly. I know a lot of these questions are stupid, but I’ve waited over 20 years for an Audi, so this car really means a lot to me. Please be gentle, I know I sound dumb. I just really wanna do it right. I slept for one hour because I spent the night reading the manual lol. I know it says high octane gas, 91 or above. I’m kind of dumb when it comes to this, I want the best of the best. Is Shell Nitro the best? What do you use? The manual suggests Castrol Edge Professional. Do I stick with that or is there something better I could get? I know this is silly, but I even researched what the best windshield wiper fluid is and I came up with Nextzett Concentrate. Is that good or should I do something else? I live in SoCal, so we get cold weather but rarely if ever freezing, do I still need antifreeze? Are antifreeze and coolant the same thing? The names suggest one doesn’t allow freezing and one cools things down, but again, I don’t know much about cars, and it’s just my 8y old daughter and I so everything I know about them is self taught, and I want to do better by her than what I had, so I’m really trying to learn all I can so I can keep our car beautiful, and pass the knowledge on to her too. ANY and all advice/suggestions welcome. Please don’t be to harsh on my ignorance here. 😅 I’ve added some photos of her as a thank you for your help. 🥹🫶🏼