All nRF5 devices have a pin crossbar that allow any digital I/O pin to be connected to any digital peripheral. You can refer to the Pin assignments and functions chapter in the product specification to see a list of all the GPIO pins. Then you configure the UART peripheral to use those pins (in software).
thank you ,i checked datasheets. i can see following
The GPIOs used for each UART interface line can be chosen from any GPIO on the device and are independently configurable. This enables great flexibility in device pinout and efficient use of board space and signal routing.
Yes, you can use any of the GPIO pins for UART. You do that in software, by configuring the UART peripheral accordingly (setting the PSELRTS, PSELTXD, PSELCTS and PSELRXD registers). In practice you will most likely not do this directly, but rather via the UART driver.
