my pet Lulu

In my 8 years old, it is the first time I met the my cat, Lulu.
I found her when I was on my way to school.
She lay by the road, so I thought maybe I can play with her for a little bit.
After a while, I was in a surprise that I don’t want to leave her alone.
So I tried my best to hide it until I finished my class that I could take her back my home.
When I attempted to bring her to my home, I found there were still a lot of cats were following me!
Because of the bad condition of their environment, I would like to take all of them to my home.
Unfortunately, my mom declined my decision, and requested me to abandon them outside immediately.
I didn't want to do what my mom said.
Therefore, some friends who love cat were willing to help me to raise these cats temporarily and looked for new masters for them.
I also made up my mind to persuaded my mom to have a cat in our house.
Fortunately, my mom believed that I would be a good keeper, so she let me keep one cat, it was Lulu.
Although Lulu have always made a mess of house, we still love her a lot.

My pet Lulu
The first time I met my cat, Lulu, (was when) I was 8 years old.
I found her on my way to school. She lay by the road, so I thought maybe I can play with her for a little bit. After a while I was surprised that I didn’t want to leave her alone. (So) I tried my best to hide it until I finished my class when I could take her back home.
When I tried [attempted] to bring her to my home, I found a lot of cats were following me! [OR there were a lot of cats following me]
Because of the bad condition of their environment, I wanted [would have liked] to take all of them home.
Unfortunately, my mom did not agree, and told me to leave them outside immediately. I didn't want to do what my mom said.
(Therefore) some friends who love cats were willing to help me to raise these cats temporarily and look for new owners for them.
I also made up my mind to persuade my mom to have a cat in our house.
Fortunately, my mom believed that I would be a good keeper, so she let me keep one cat: it was Lulu.
Although Lulu has always made a mess of the house, we still love her a lot.

my pet Lulu  (I'm going to write this as past tense)

In my  I was 8 years old it is the first time I met the my cat, Lulu.
I found her when I was on my way to school.
She lay by the road, so I thought maybe I can could play with her for a little bit.
After a while, I was in a surprised that I don’t didn't want to leave her alone.
So I tried my best to hide it until I finished my class that so I could take her back my home.
When I attempted to bring her to my home, I found there were still a lot of cats were following me!
Because of the bad condition of their environment, I would like wanted to take all of them to my home.
Unfortunately, my mom rejected declined my decision, and requested instructed me to abandon them outside immediately.
I didn't want to do what my mom said.
Therefore, Some friends who love cat were willing to help me to raise these cats temporarily and looked for new masters owners for them.
I also made up my mind to persuaded my mom to have a cat in our house.
Fortunately, my mom believed that I would be a good keeper, so she let me keep one cat. It was Lulu.
Although Lulu have has always made a mess of house, we still loved her a lot.

Notes: Declined is more of not accepting an offer.  For example, "I invited my friend to dinner, but she declined."  Rejected is more like you tried to do something and the other person blocked you.

requested is like asking nicely hoping you will do it.  Instructed is more direct, leaving no choice by to comply.