The dragon, that ancient serpent, who is the devil and Satan - THE GREAT DECEIVER of the 10 Commandments, page-3

You obviousy can't break a law that you have not been provided so no.

Yes "gentile" Christians are under God's law. The new Israel comprises of all that are Christ's no matter their geographical location in the world.
Galatians 3:28-29 “There is neither Jew nor Greek, there is neither bond nor free, there is neither male nor female: for you are all one in Christ Jesus. 29 And if you be Christ's, then are you Abraham's seed, and heirs according to the promise.”

See below link for more in depth explanation:
https://www.the-ten-commandments.org/isthesabbathonlyforisrael.html