I moved your thread.
It's impossible to quote each sentence from pictures. I added corrections in the written order. Please ask if it's unclear what part I'm talking about.
The first composition;
It's more natural to add あと or それと before 猫.
両親 is more appropriate.
There is a typo in イタリア人てす.
You can't use honorifics for your in-group members, thus, ブルノさん is inappropriate. Also, ブルーノ is more common for Bruno.
高いではありません is ungrammatical. 高い is an i-adjective, not na-adjective.
モニカさん is inappropriate, either.
Your mother is not male.
落ち着いたです is ungrammatical.
There is a typo in 作くこと.
は is more appropriate for contrast.
レティジャさん is inappropriate, either.
妹は私より若いです。 is obvious. 妹, i.e., your younger sister can't be older than you. You don't need to say it.
低い can mean that another thing than the height is low, e.g., your younger sister's income is lowest in your family. 背が低い is more appropriate.
You don't need to use two nominalizers in 絵を書くのこと. The kanji 描く is used for "to draw/paint a picture".
は is more appropriate for contrast also in this sentence.
The particle is wrong, and a article is lost in 彼女が鼠嫌いです.
The subject is unclear in the last sentence.
