You need a SIM card, so buy one (postpaid or prepaid) or take a subscription from a Service provider.
You need to charge the battery > 70%.
It’s asking Itunes codes etc
👉You did not read my previous post.
So once again ⤵️
Or use your Apple ID balance as payment method:
Add money to your Apple ID balance
Add money to your Apple ID balance – Apple Support (UK)
What you can buy with your Apple Gift Card or Apple ID balance
What you can buy with your Apple Gift Card or Apple ID balance – Apple Support (UK)
How to redeem your Apple Gift Card or App Store & iTunes gift card
How to redeem your Apple Gift Card or App Store & iTunes gift card – Apple Support (UK)
Where to buy:
Actually, you can buy an Apple gift card at many places, it depends of course on where you live.
At an Apple Store or an Apple Authorized Reseller in your region certainly, but also at a good bookstore, supermarket and/or drugstore.