Operating two functions simultaneously
Is it unable to operate two operations simultaneously?


The only way you can do two operations simultaneously is to have two Arduinos. An Arduino can only do one thing at a time. In order to make it seem like it's doing things at once you have to create your sketch accordingly. The use of delay() is right out. As are long loops using things like while(). In short: anything that blocks is bad.


  Can we use these two sentences in one code?


Not reliably, no.  They are both resource hungry and, to a large extent, blocking. A general rule is, if you need at least two more UARTs than the board provides then you need a different board. You can only reliably work with one software UART at a time.

I would suggest upgrading to a more capable board with more hardware UARTs. Either that or use a bluetooth system that doesn't use UART, such as an SPI based BLE module.