iPhone 16 Pro Max was fully discontinued by Apple a year ago, when iPhone 17 Pro was released. And now that Pre-Orders will begin for iPhone 18 Pro in two days, iPhone 17 Pro has now been discontinued by Apple. We can't help you purchase a phone which hasn't been manufactured by Apple in a full year now.
If that is truly the phone you want, you'll need to find a used one, which is not recommended unless you buy an Apple Refurbished 16 Pro Max from Apple directly. You'd need to check with local sellers in Ukraine (if that is where you live). If you do purchase a used iPhone, read this --> The All Too Common SAD Reality of Buying … - Apple Community