Hi. I am buying an apple watch to use outside the USA. If I pay the full price, does it automatically come unlocked and does it connect with my iphone as long as I have a working sim card and internet? Thank you.

DO NOT buy a cellular version of Apple Watch in North America and expect it to work in other countries. The North America cellular region uses a unique set of radio frequencies which are not supported anywhere else in the world. Take a look at the table in https://www.apple.com/watch/cellular/ to see the model numbers for different regions.

The cellular versions of the Apple Watch are not really locked, but they are regional devices. The devices will only work with cellular their respective regions. The US version of the Watch will only connect to the carriers listed in this support document. https://www.apple.com/watch/cellular/ If you are going to travel outside the US, your probably will not be able to connect to cellular.