FreeRTOS DATA logging

I have ported Freertos to Teensy 4.1, please tell how to logdata in a file( text or excel) in teensy 4.1 using freertos.

If you are asking for file system support on Teensy, I’d recommend reaching out Teensy developers. A quick Google search produces this which may be useful to you - Using file system with Teensy 4.0 | Teensy Forum.