This is what I found from a quick Google Search. There doesn't seem to be a permanent way to keep that percentage next to the battery. Obnoxious, I know.
How to show battery percentage on iPhone 11
- Open Control Center (swipe down from top right corner)
- From the Lock screen or Home screen, swipe from left to right, and you’ll find the battery percentage near the top of the Today View screen
- Ask Siri
- Plug in your iPhone, and you’ll momentarily see the percentage show on the Lock screen
Here’s how these steps look in practice:
Here's the original link:
https://9to5mac.com/2019/08/20/show-iphone-battery-percentage/