In Julius Caesar, were there 3 shouts praising Caesar?Or were there 2 shouts praising him and the third was the crowd booing?
It is always a good idea, when asking about a specific moment in a play to cite the Act and Scene to which you refer. I will assume here that you refer to Act I, scene ii when, as Brutus and Cassius talk, there are shouts heard offstage from the direction in which Caesar has gone to observe the games.
The number of shouts that are heard by Brutus and Cassius is, dramatically, an interesting question. It is most important to refer to the text, the lines spoken by the characters, when determining action or sound effects. Shakespeare, if he intended that some necessary action or sound occur, always had characters make reference to it. We have no proof of any kind that stage directions you might find written in your edition of each play were, in fact, the work of Shakespeare. So, it is always the safest course to rely on the words spoken by the characters.
During his conversation with Cassius in Act I, scene ii, Brutus mentions the cheering of the crowd twice. The first mention is at line 78:
What means this shouting? I do fear that people
Choose Caesar for their King.
And again at line 132:
Another general shout!
I do believe that these applauses are
For some new honours that are heap'd on Caesar.
Shouting is not mentioned in the scene again until Caesar has re-entered and exited, leaving Casca alone onstage with Brutus and Cassius. They talk about what Casca witnessed.
Why there was a crown offered him. And being offered him, he put it by with the back of his hand, thus. And then the people fell a-shouting.
What was the second noise for?
Why, for that too.
They shouted thrice. What was the last cry for?
Why for that too.
Was the crown offered him thrice?
Ay, marry, was't, and he put it by thrice. . .
So, though, during the time that Brutus and Cassius are alone onstage, Brutus only remarks upon two shouts, Casca confirms that there were three, and they were all in relation to Caesar's being offered and refusing of the crown.
As Casca tells the story, the shouts happen in this way:
. . .the rabblement hooted and clapped their chopped hands and threw up their sweaty night-caps and uttered such a deal of stinking breath because Caesar refused the crown that it had almost choked Caesar. . .
However, we cannot assume the nature of these shouts simply by reading the play. What sort of "shouts" they are would be something each production of the play would decide. Are the shouts Caesar's supporters? Detractors? Some of each? The script cannot really confirm this, since we only have Casca's re-telling of the events to inform us, and he is hardly a disinterested bystander.
So, in answer to your question, whether all three shouts are the same or are each of a different kind of response, is not something that reading the script alone can confirm. This sort of information must be gained from experiencing the play as Shakespeare meant it to be experienced -- as a live performance.
For more on this scene, please follow the links below.