I would say the regular iPhone 12 but you mention your budget is limited, so for the best mix of battery life and usability the iPhone 11 wins. Although you do end up with a not as sharp or bright LCD screen and no 5G, but the phone is still plenty fast, solid battery life and great cameras while having night mode on the main sensor. The 12 mini has atrocious battery life and he SE isn’t much better while having a dated design.