If you are in the Federated States of Micronesia then note that there is no British Embassy in the country. Should you need assistance then you will need to contact the British High Commission in Fiji for assistance. You will need to contact them for an emergency passport if you lost your passport.
Register a Birth Abroad:
The British High Commission does not deal with this and you will have to do it yourself. You need to download the needed documents and send it back to the UK for processing. You can see the born abroad post on this website here.