For the Expression of Interest go and visit the OINP home page and you can see all the details there. Once you apply for the EOI you have to then apply for the nomination and only when you receive the nomination then you come to the IRCC PR application portal link. Its not in GCKey at this stage (you will use gckey later when you link your PR application to gckey, but much much later)I am preparing to apply, is it same gckey website or different IRCC website?