if anyone could explain it to me it would be very helpful

you need to rank up and finish all missions and reach the rank of marquess. After that, if you have the most influence in your nation among all nobles, you become king at update. If someone else is also a noble, and has more influence then you, you will instead become a governor of port or a duke depending on how you rank. Each nation can have 10 duke/duchesses. and can have 1 governor per port. So if 11 people have more influence then you, have finished all missions and no ports for governors, you end up staying at marquess rank until you pass someone.

1) Become Marquess of that nation
2) At server midnight, have more total influence than any other player in that nation

thank you