Who comes to visit Brutus in his backyard what do these individuals want?

Act II, scene I begins with Brutus pacing up and down his yard, questioning his reasons for assassinating Caesar. He has no personal vendetta against Caesar, but seems convinced that he must kill him for the sake of the people. He is interrupted by his servant Lucius who tells him that Cassius has arrived with a group of men with “half their faces buried in their cloaks.”
Cassius introduces them as Trebonius, Decius Brutus, Casca, Cinna and Metellus Cimber. As fellow conspirators, they have come to plot the assassination of Julius Caesar.
Before they begin their discussion, Cassius wants them all to swear on an oath. Brutus, however, declines, saying

No, not an oath: if not the face of men,The sufferance of our souls, the time's abuse,—If these be motives weak, break off betimes,And every man hence to his idle bed;

They start their discussion by debating whether they should bring Cicero on board. The five men think it would be a good idea:

O, let us have him, for his silver hairsWill purchase us a good opinion

Again Brutus declines:

For he will never follow any thingThat other men begin.

Next they debate whether they should kill Anthony as well. Brutus agrees that Anthony could cause them problems, but thinks “our course will seem too bloody.”
Finally, Decius offers to bring Caesar to the capitol where the assassination will take place.

Let me work;For I can give his humour the true bent,And I will bring him to the Capitol.

However, Cassius says they will all go to meet him. They will meet again the next day at the “eighth hour.”

In Act Two, Scene 1, Cassius and the other senators conspiring against Julius Caesar arrive at Brutus's home wearing cloaks that cover their faces. The conspirators visiting Brutus's home include Cassius, Casca, Decius, Cinna, Metellus, and Trebonius. Cassius proceeds to introduce the senators conspiring against Caesar to Brutus, who politely shakes their hands. When Cassius suggests that the senators swear an oath, Brutus argues that there is no need for an oath because they are justified in carrying out the necessary task. The senators then discuss whether or not they should include Cicero in their plan to assassinate Julius Caesar, but Brutus decides against it. Cassius then suggests that they also kill Mark Antony, but Brutus argues that the Roman populace will think they are too bloody. After Decius tells the conspirators that he will convince Caesar to visit the Senate, Brutus reminds the senators to appear happy, and the conspirators go their separate ways.