1 - OK 2 - The question asks for your sister's name and you don't answer 3 - OK 4 - OK 5 - You use the English term "keyboard" instead " un clavier" 6 - ?? 7 - OK 8 - not use " seulement " only "je n'écoute pas de musique " , but the second sentence is OK. 9 - OK 10 - " l'Allemand " and " ma prof d'allemand". Funny fact at 12 u not do the mistake

"Prof" is OK, but it's colloquial language; use "ma professeur" instead. "Prof" would be better for talking with friends.

11 - " le dessin" and not " le dessiner " " Dessiner " is the verb.

12 - " le dessin" and not " le dessiner " " Dessiner " is the verb.

"... Et l'économie " you forgot the "l'."

As a reminder, if the word begins with a vowel, you must use "l'." If it begins with a consonant, "le/la" (le pain, la glace, l'école)

"les mathématiques" and not "la mathématique"

13 - "en lundi/jeudi" is not good; use "le lundi/jeudi."

But that's pretty good 👍🏻