I usually walk Along the beach.
And I also like to make sandcastle!
But It is really simple, it is round and it has one hole through it.
So it is more like sand cave.
And I like to eat snacks at the beach.

“Let Us Not Grow Weary of Doing Good” — Galatians 6:9
= 
I usually walk along the beach.
And I also like to make sandcastles!
But it is really simple; it is round and it has one hole through it.
So it is more like a sand cave.
And I like to eat snacks at the beach.
= "along" and "it" are not proper nouns, so they should only be capitalized if they are the first words of a sentence.
= When talking about an activity or hobby in general, we often use the plural form of countable nouns. 
= Great job!