To deploy and see your webpart in the sharepoint site, pls follow the instruction given in the following link.
Here is the steps to debug a web part in SharePoint :
Step 1: open the project and set the appropriate breakpoints.
Step 2: Create a Web Part Page on the default SharePoint site.
Step 3: Add the Web Part to the page.
• Attach the debugger to the W3wp process.
• On the Debug menu in Visual Studio .NET,click Processes.
• Verify that the Show system processes check box is selected.
• Verify that the Show processes in all sessions check box is selected.
• Under Available Processes, click W3wp.exe in the Process list, and then click Attach.
• Under Choose the program types that you want to debug, select Common Language Runtime, and then click OK, Then Close
Hope this helps you,
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