I found the solution myself in the post.
viewtopic.php?t=2045

Good afternoon!
I have installed ubuntu linux on my Lyra Ultra.
Using luckfox-config, I configured UART1,2,3
Here are the contents of the luckfox.cfg file
TP_STATUS=1
I2C2_STATUS=1
I2C2_SCL_RM_IO=1
I2C2_SDA_RM_IO=0
UART1_STATUS=1
UART1_RX_RM_IO=13
UART1_TX_RM_IO=14
UART2_STATUS=1
UART2_RX_RM_IO=11 ...