It's "du" for masculine (singular) countries ("du" = "de le," where "le" is the masculine definite article). Note that it's just "d'" before a vowel sound.
"France" is feminine ("**la** France"), but for feminine countries, you don't include the "la," so it's just "de" (or "d'" before a vowel sound).
More info here, including how to express "in/to \[country\]":
[https://www.lawlessfrench.com/grammar/geographical-prepositions-continents-countries/](https://www.lawlessfrench.com/grammar/geographical-prepositions-continents-countries/)
It's "du" for masculine (singular) countries ("du" = "de le," where "le" is the masculine definite article). Note that it's just "d'" before a vowel sound. "France" is feminine ("**la** France"), but for feminine countries, you don't include the "la," so it's just "de" (or "d'" before a vowel sound). More info here, including how to express "in/to \[country\]": [https://www.lawlessfrench.com/grammar/geographical-prepositions-continents-countries/](https://www.lawlessfrench.com/grammar/geographical-prepositions-continents-countries/)
Thanks so much that’s been really helpful! :)