Sync it to iTunes.
Plug in your iPhone. Connect to iTunes. Click Sync.
After you buy the music in the itunes store you have to sync it.
I had this problem too. I had iTunes installed already, but when I tried to sync my iPhone, nothing came up on my iPhone screen. I quit iTunes, and unplugged my iPhone, then plugged it back in and opened iTunes again.
You have to Sync it with iTunes.
Via iTunes, add the .ipa files to iTunes Library and sync with the iphone
Through iTunes on your PC or Mac. In there you sync it, with your iPhone.
You plug your iPhone into your computer, and then on the left it will say the name of your iPhone, right click on it and left click transfer purchases, and your done in Itunes.
You can as long as you have authorised your MacBook via iTunes.
Yeah, put it into Itunes and sync it with iphone
Well, to install iTunes on your computer you don't have to use your iPhone. You just go to the Apple website, and search iTunes, and then you can just download it from there. If you want to sync your iPhone with iTunes to back up your content, you just sign in with your Apple ID (if you have an iPhone you should already have one), then plug in your iPhone and press sync.
To get iTunes content on your iPhone, you don’t actually install iTunes on the device itself, since iTunes is a desktop app for Windows or Mac. Instead, you use iTunes on your computer to sync or transfer music, videos, apps, and other media to your iPhone. Here’s how: Install iTunes on your computer: Download the latest version from Apple’s website and install it. Connect your iPhone: Use a USB cable to connect your iPhone to the computer. Open iTunes and ensure your device is recognized. Sync content: In iTunes, select your iPhone icon. Navigate through the tabs like Music, Movies, TV Shows, or Books. Check the content you want to sync, then click Apply or Sync. Transfer purchases: To add items already purchased on the iPhone, go to File > Devices > Transfer Purchases from [your iPhone] in iTunes. Use iCloud alternatives: For wireless syncing, you can enable iCloud Music Library, iCloud Photos, or use Finder on Mac (macOS Catalina and later) to sync content without iTunes. Following these steps will get your iTunes media onto your iPhone efficiently, keeping your music, videos, and other purchases up to date.