How can I improve my iPhone 11Pro battery life?

Batteries degrade over time with usage due to chemical aging, that's just how they work.

You can expect about a 1% drop per month with average use on an iPhone. This is an approximation, that is why it may be plus or minus a few percent on a month to month basis.

Apple recommends replacing it when it reaches 80%. To check your battery health, go to Settings > Battery > Battery Health.

iPhone Battery Replacement.

iPhone Battery Service - Apple Support

About Lithium Ion Batteries

iPhone battery and performance - Apple Support (IN)

Do you have a question or did you just want to vent? You don't say how long you've owned your iPad, but iPad 11 Pro was first released in 2018, 6 years ago. If your iPad isn't holding a charge and it's an original 11 Pro, it may be time to schedule a battery replacement with Apple?

When was the last time that you replaced the battery in the iPhone 11 Pro?