Hi,
Go to settings > reading and change the ‘blog page show at most’ to whatever number you want.
That will change how many appear on each page.
To change how many appear in a row you need to go to:
appearance > editor > and within the Stylesheet.css (which should be loaded automatically) search for this set of code:
.hentry {
float: left;
margin: 10px;
padding: 0;
position: relative;
width: 180px;
height: 180px;
simply change the 180 to whatever size, smaller or larger, until your desired amount of circles appear.