[Grammar rule] You wrote 勉強します, but I would write it 勉強しています. English verbs with present tense that refer to your regular action like an occupation or a habit must be said with Te-form in Japanese. i.g.) I teach Japanese at school. 学校で日本語を教えています。 If you need more explanation about this grammar, you can read it with this link. https://archive.org/stream/Genki/Genki%20-%20Elementary%20Japanese%20I#page/n169/mode/2up About how to improve listening skills, I am sure that speaking practice makes perfect. If you could speak in Japanese as fast as Japanese natives do, you would have been able to listen to Japanese natives. That means that only watching and listening aren't good enough to improve your listening skills. You should practice pronouncing as same as Japanese natives do many times with a CD, a video, or something, repeating again and again. It takes a long time to get used, but that makes you perfect.

My pleasure.

Thank you all so much for the advice and corrections!

みんな（みんな→みな）さんこんにちは。アシュリーです。日本語を勉強するのが好きです。一週間に三回日本語を勉強します。12月に日本語能力試験が（が or を）受けたいです。