FPGA's and SoC can be used for many more advanced functions as making a LED to blink. However "LED Blinky" is considered a "Hello World" for systems that can not otherwise say Hello.
To make LED to Blink (under user control) following requirements are needed:
If any of those requirements are missing, you will most likely fail with the simple task to get an LED to Blink.
It is very common that modern Integrated Circuits have separate power supply pins for I/O Voltage. That voltage if applied control the output levels from the device, if the Voltage is too low or missing then it is not possible to have enough current from the device I/O Pin to make a LED Lit.