You can create a new solution for each project or place multiple projects in an existing solution.

To create a new project in an existing solution:

1. Choose Project > Add New Project.
2. In the New Project wizard, select the type of project you wish to create and specify where it will be placed.
3. Ensure that Add the project to current solution is checked.
4. Click OK to go to next stage or Cancel to cancel the project's creation.

The project name must be unique to the solution and, ideally, the project directory should be relative to the solution directory. The project system will use the project directory as the current directory when it builds your project. Once complete, the Project Explorer displays the new solution, project, and files contained in the project. To add another project to the solution, repeat the above steps.

To create a new project in a new solution:

1. Choose File > New Project or press Ctrl+Shift+N.
2. Select the type of project you wish to create and where it will be placed.
3. Click OK.