I don't know about to write, and for it.

Combining below.

I'll to write about my cats: ¶
¶
¶
I have two cats, Alisse and Ash.

Let's combine the two sentences into one:
I don't know what to write about so I'll write about my cats. I have two cats: Alisse and Ash.

Alisse is more than three years old and Ash is five months.

Ash is the Alisse's daughter.

Alisse has three colors: white, black and orange (aslike the cat ofin the pixar's movie: Soul).

como translates into as, like, how, and more in English.
When adding information, like you did above, I think "like" is used always.
"He was really tall, like Andre the Giant!"
"She has a lot of trophies, like a professional tennis player!"
"He makes a lot of mistakes but he's really smart, just like Einstein!"

She has green eyes, alsond her daughter does too.

She and her daughter both have green eyes

I don't know abouwhat to write, and for it.bout today.

So, I'll to write about my cats: ¶
. ¶
¶
I have two cats, Alisse and Ash.

Alisse is more than three years old and Ash is five months old.

Alisse has three colors: white, black and orange (aslike the cat ofin the pixar's movie: Soul).

She has green eyes, alsos has her daughter.

And Ash is gray.

I don't know abouwhat to write, and for ibout.

I'll to write about my cats: ¶
. ¶
¶
I have two cats, Alisse and Ash.

Alisse is morea little over three years old and Ash is five months old.

Depending on how you want to express this, typically we might say the pets average age +/- 1/2 years. For example "Alisse is about 3 years old." or "Alisse is 3 1/2 years old." I'm not sure how it is outside the US but we don't generally worry too much about other in between unless the pet is young, like Ash. Then we would use months as you have done. Once Ash gets to 11 months old, we might say "Ash is almost a year old." or "Ash is about a year old now."

Ash is the Alisse's daughter.

Alisse's fur has three colors: white, black, and orange (aslike the cat of thefrom pixar's movie: Soul).

She has green eyes, alsos well as her daughter.

Could also say "Both cats have green eyes." or "Alisse and Ash both have green eyes."

And Ashsh's fur is gray.

Logically this would be better to put after Alissa's fur color is described. Grouping the topics (fur color in this case) together when writing is usually a good thing to do.

I don't know about to write, and for itso I'll write about my cats.

connect to the next sentence

...so I'll to write about my cats: ¶
¶
. I have two cats, Alisse and Ash.

Continuing the connection from the last sentence. All together: "I don't know what to write, so I'll write about my cats."

Alisse is more than three years old and Ash is five months.

Ash is the Alisse's daughter.

Alisse has three colors: white, black, and orange (same as the cat of the pfrom Pixar's movie: Soul).

Pixar is a noun (company name), and so is capitalized.

She has green eyes, alsond so does her daughter.

And Ash is gray.

I don't know abouwhat to write, and for ibout.

This is the right order for the words. If you mean you don't know what to write 'for it', that is understood when you say you don't know what to write.

So, I'll to write about my cats: ¶
¶
¶
I have two cats, Alisse and Ash.

So, makes it flow better and transition from your last sentence.

Alisse is more than three years old and Ash is five months.

Ash is the Alisse's daughter.

Alisse's fur has three colors: white, black and orange (aslike the cat of the pixar's movie: Soul).

Alisse herself refers to the skin of the cat so saying fur is more accurate.

She has green eyes, also does her daughter.

And AshHowever, Ash's fur is gray.

You can't start a sentence with and in traditional written English.