How new is the phone @skyray29
I'm asking as the phone could still be updating and adjusting to your usage habits.
In the early stages your battery will also be still learning.
There are threads on the forum in regards to phone's overheating.
A phone is overheating if you get a message onscreen and typically forces an auto shutdown.
Other than that it's warming up due to internal processes and the heat is being channeled away from the chipset by the phone's internal cooling system.
Current Phone ~
Samsung Note 20 Ultra 5G SM-N9860_256Gb SnapDragon 865+
Samsung One Ui 3.1/ Android 11.