Confirm device model
In a world of planned obsolescence, we are taught that "old" means "useless." But the reminds us that hardware only dies when we stop dreaming.
If you're looking for a caption or post to share this process with a tech community, here is a "deep" take on breathing new life into old hardware:
Unlock bootloader / Enable Developer options and USB debugging
The official firmware for the Samsung Galaxy Tab 2 10.1 (GT-P5100) peaked at Android 4.2.2 Jelly Bean. To run Android 7.1.2 Nougat , you must use a custom ROM, with LineageOS 14.1
The keyword "download samsung tab 2 101 gtp5100 android 712 firmware best" points to several sources. However, you should only download from trusted developer forums to avoid malware.