Hi, Abdulsalam.
I'm glad you decided to reach out on the Apple Support Communities forums today. If I understand correctly, you purchased an iPhone 11 and a Belkin wireless charging pad, and you’re curious about your iPhone getting warm when it’s charging. I'd be happy to address your concerns.
It's not uncommon for your iPhone 11 to get warm while it's charging, especially right after you set it up for the first time or restore from a back up.
Check the “Learn more” section of this article: How to wirelessly charge your iPhone
"Your iPhone might get slightly warmer while it charges. To extend the lifespan of your battery, if the battery gets too warm, software might limit charging above 80 percent. Your iPhone will charge again when the temperature drops. Try moving your iPhone and charger to a cooler location."
The "Your device might get warm" section of this article may also offer an explanation: Keeping iPhone, iPad, and iPod touch within acceptable operating temperatures
"When you use the device or charge the battery, the device might get warm. You might notice that your device feels warmer in these situations:
- When you set up your device the first time
- When you restore from a backup
- When apps reindex or reanalyze data, like Photos tagging for faces, places, or keywords after a software update"
Hopefully this helps put your mind at ease about your iPhone!
Best Regards.