Hello
Hope you are well.
For doing this you have to initialize other instance of LPUART since LPUART1 that is used does not have a connection to the Arduino pins. To do this you can use the Config Tools to route the pins and configure the peripheral.
Omar_Anguiano_0-1633023827441.png
Let me know if this is helpful, if you have more questions do not hesitate to ask me.
Best regards,
Omar