I want to connect my rectangle thing in the center to the two concentric circles and make one single entity so that I could extrude it later into a part. However, I'm unable to erase the parts of arcs to connect them to the rectangle. How do I do this?
I just got Solidworks a day ago, so I'm sorry if this is a stupid question.
The direct answer to your question is to use the Power-Trim tool to remove the sections of arcs that intersect the rectangle.
This is one of the basic techniques that are covered in the tutorials included with SoilidWorks.
Before proceeding to do design work, you should go through all of the basic tutorials-there are around 30 of them. They can be accessed through the Help pulldown menu (the little question mark icon in the header of the Solidworks program window)
-and if you really want to excel with this software, you should take a structured training program-either the essentials training offered by your SolidWorks VAR or one of the many good online courses available.