Good evening! About Mmy aunt Good evening! About my aunt

In formal titles, each word has to start with a capital letter (besides a, to, but, yet, or so - unless one of them is the first word of the title): Good Evening! About My Aunt but if you are writing an informal title, you don't have to capitalize all of them, only the first word, so: Good evening! About my aunt would be correct.

At 6 PM 6 o'clock, my aunt and I went on a walk. At 6 PM, my aunt and I went on a walk.

It's either: 6 PM or 6 o'clock you can't combine the two

At PM 6 o'clock PM, my aunt and I went on a walk. At 6 o'clock PM, my aunt and I went on a walk.

When I checked my homework with using my personalon my computer, my aunt passed gas. When I checked my homework on my computer, my aunt passed gas.

Nobody really says "personal computer", just "computer" :) Also, you usually say that you "check something on the computer", not with

When I checked my homework with using my personal computer, my aunt pass gas. When I checked my homework using my personal computer, my aunt pass gas.

Hers pass gas smellsed badly. Her gas smelled bad.

You were using past tense before, so I changed smells -> smell "pass gas" is an action. You're just talking about her gas, so you just say "Her gas smelled bad."

Hers pass gasIt smells (very) badly. It smells (very) bad.

When she passes gas, I always run away from her. When she passes gas, I always run away from her.

When she pass gadoes this, I always run away from her. When she does this, I always run away from her.

Why idoes her pass gas smells so bad? Why does her gas smell so bad?

Why idoes her pass gasfart smells so bad? Why does her fart smells so bad?

BecausSince I am going to live with her from September, I will have to be more careful it. Since I am going to live with her from September, I will have to be more careful.

It sounds better with since. https://dictionary.cambridge.org/grammar/british-grammar/as-because-or-since - this explains the difference between since/because.