Can you deactivate 5G on iPhone 12?

Choose the Voice & Data option. 3. Tap on the LTE option to switch off the default 5G Auto and make your iPhone 12 roam with 4G connectivity only. 4.6 Tem 2021

How to turn 5G on/off on iPhone 12

How to switch between 5G and 4G LTE on your iPhone 12