My favorite ice cream is chocolate flavor.
1. It is so sweet.
2. It like a real chocolate.
3. It's like sugary. (It has the same thought with the first sentence or reason.)
So, that why my favorite ice cream is chocolate.

CORRECTIONS:
1. Please, be mindful of the proper spacing of some words when you are writing a composition. example: icecream - ice cream
2. We could include the word "flavor" in our sentence if  the order of words will be change to this pattern >> My favorite ice cream flavor is chocolate.
3. We don't need the word "like" for the third sentence it doesn't function as modifier nor a verb.

Hi, Ellie!
Thank you for doing your homework. I hope we'll be able to discuss my corrections later. See you!
-Teacher Joanna