Lift the bonnect and locate the two bolts holding the engine cover on. Remove the two bolts at the front of the cover circled in Yellow using an 8mm spanner or socket and ratchet.
Lift the cover off the engine once the two bolts are removed from the front, it has a locating peg under the rear edge of the cover that allows the cover to pop off and back on.
With the cover removed you can gain access to the ECU bolted to the bulkhead of the car, gently pulling the wiring loom you can release the clips holding the loom to the ECU studs.