Thank you! That topic particle 는 and 은 can be tough at times. I used 는 because I was typing/writing. I understand that 은 is used when speaking, right?

I'm also lost on "...스물 여섯살". Is this another way of saying my age? I still haven't figured that bit out yet. Thank you!

P.S.
Did you mean to say "If you keep learning Korean, your Korean WILL be better?"

When you say your age in an another way, You can say "이십육".
I understand that you sometimes feel confused when you choose to write between 은 and 는. In fact, I also have difficulty in explaining between 은 and 는. When we use 은 and 는, there is no specific rule which can apply to sentences. It depends on subject.
At the moment,you can't understand what I say exactly. But if you try to read Korean books or articles,you would happen to know how to use exactly someday.

P.S. Yes:) I learned must be is strong guess,am I right?
My sentences are wrong?