Why when you tap the word ' my ' , the translation there is моя , but when you type it like that, it's wrong?
So it's not the person speaking that makes it masculine or feminine but the noun?
Why is дом мой wrong? I thought it doesn't matter which word is first in Russian language
Because when you change the order the meaning changes to "the house is mine"
Between мой and моя, its often rhyming. E.g. моя мама, моя водка. Otherwise мой. When this may not be true is for мой папа, because its masculine, u jsut ignore the rhyme there :p hope this helps as a beginner rule of thumb.
Я значит одна знаю русский, на Дуолинго учу английский, а сюда зашла просто посмотреть.