Power sequencing in FPGAs and MCUs
Each evaluation board must have the right power stage ready to power sequentially each of the voltage needed for the FPGA or MCU.

You can take a look in the schematics of your EVBoard (usually available in manufacturer website). The power stage of your EVBoard should have some DC/DC converters (or lineal regulators) each of them with a EN pin (or another similar behaviour name).

With these pins could be defined a chained power-up strategy. Asserting each with a previous powered voltage in the order established at the datasheet.

Also, it's possible use a voltage supervisor chip that assert the EN pins in a defined way.

A more analogical way is use a RC circuit to time the assertion of EN pin.

In conclusion, don't worry about the power sequence of your EVBoard, it has been correctly designed by manufacturer.
You must take it into account in your own FPGA or MCU pcb design.

Best regards