"In one year"
Translation:En un año
"En uno año" is wrong. The correct form is "un". "Uno" is a pronoun and "un" is a determiner. A pronoun is a word that can stand instead of noun. So for example, in the sentence "I have one too", "one" is a pronoun because it can stand instead of noun (I have a shoe too). In Spanish, this sentence would be "Yo tengo uno también".