Apple typically releases its major iOS updates alongside the launch of new iPhone models, and this pattern is likely to continue with the iPhone 13 and iOS 16. Therefore, it’s reasonable to expect that the iPhone 13 will come pre-installed with iOS 16 upon its release in the fall of 2023. Keep an eye on Apple’s official announcements and
iOS 16, the next OS upgrade for the iPhone, was the most talked-about topic during the WWDC 2022 Keynote.The new version brings many features, prioritizing personalization and sharing the most.
I saw a site called betaprofiles.com, where you can download and install beta versions of ios, iPadOS etc. I didn't try it myself yet, but I would recommend that you would first make a backup of your phone, beacouse in case something goes wrong, you wouldn't lose all your important data. IIRC, that site eases the way to install OS versions the Older iPhone Models Won’t Get iOS 16 Although the release of iOS 15 in 2021 didn’t see any major changes from the release of iOS 14 in 2020, that’s not quite the case this year. With the iPhone 8 series now the new barrier of entry, those with an iPhone 6s, iPhone 6s Plus, iPhone 7 or iPhone 7 Plus won’t be eligible to upgrade to iOS 16.