It is like a dog, it is as if it is a dog. They are just levels of comparing. https://www.youtube.com/watch?v=6nDEvB5eWDU

Both are synonyms, you must know, but they are used in different situations, I am going to tell you how to use them correctly. Like. it expresses "similarity", it compares things. He works {like} a professional. (it means that he is not a professional, but he works as if he were though) He works {like} a doctor (he is not a doctor, but he works as if he were one) As. It does not compare things, it expresses that something {is} something. He works as a doctor (it means he does not only work like a doctor, he is a doctor) He works as a slave (he does not only work like a slave, he is a salve). Hope I have helped you.

You should word this question like so: What is the difference between 'like' and 'as'?

Like...as if. Just kidding :)