To be honest,it is a little complex.Here I can only express my understanding to you. “这样”means 1.like this/this way eg.这样，你来吧。 2. To describe something eg.这样大的石头他还是头一次见过。It is the same as“这么” “这个”means:this or this one.It refers to human or object. “这”is a pronoun. “这是”means:this is.Its construction is subject+verb. You'd better find a Chinese-English dictionary to carefully read it.Hope this can help you!

这样ack like this . 这个this ( one of a lot ) 这this 这是this is .