Hello VintageMind2024,
We see you've posted a possible issue with your new iPhone getting warmer than expected during use. We'd like to go through some tips and steps to make sure it is operating within the acceptable temperature range. First, do you get any alerts about the temperature being too hot? If so, look over our guidance here: If your iPhone or iPad gets too hot or too cold - Apple Support
If you aren't getting any temperature alerts, let's look at specifics to help identify what might be going on. Determine where you notice the warmth on your iPhone. Does it seem to be around the camera, on the front, near one side? Then, take note of any specific app you might be using at the time. Also consider if it occurs while you are charging it and if you are charging it wirelessly or wired.
We also have guidance to get the most out of your battery performance, which can also be impacted by temperature: iPhone Battery and Performance - Apple Support
Best regards.