Remove 100% battery indicator rectangle from lock screen wallpaper

To improve my understanding of the phenomenon, it would be highly beneficial if you could share a full screenshot (Do not crop it). Visual representations carry a greater impact than written descriptions.

Please remember that this is a public forum, so when attaching a screenshot, please avoid including any personal credentials such as IP addresses, card details, email IDs, Apple IDs, IMEI numbers, serial numbers, phone numbers, order IDs, or any identifiable location information if you are sharing a map.

With the limited information that you have provided, It is hard to even guess the problems faced by you. 

You may get faster and better responses to your query by --> Writing an effective Apple Support Commun… - Apple ...

Please re-post with detail so that someone else can help.

Edit a widget stack

1. Touch and hold the widget stack.
2. Tap Edit Stack. From here, you can reorder the widgets in the stack by dragging and dropping the app where you want it in the stack. You can also turn Smart Rotate* on or off.
3. 
   
4. 
5. Tap the Done button.

* When Smart Rotate is on, iOS shows you relevant widgets throughout the day.

You need iOS 14 or later to use Smart Stacks or create your own widget stacks.

How to add widgets to your Lock Screen · Touch and hold the Lock Screen until the Customize button appears, then tap Customize. · Tap Add ...Read more

How to add and edit widgets on your iPhone