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Welcome, I'm Chris (aka Moose), my normal schedule online is around lunch and after dinner till early morning.
With the engine running, battery light on, what is the voltage at the battery posts?
Those readings indicate your alternator is not charging.
Confirm the black wire to the alternator is showing battery voltage.
If that is okay then a scan tool is needed to check for codes in the vehicle electrical systems control module and engine control module. These 2 modules control the charging output of the alternator. Can you do these things.
Thanks for using Just Answer, and rating me so I am compensated, Chris