Which program in Visual Studio lets me look into DLLs to see its API?

See the question. I want to see the methods and classes offered by a DLLs library.

How can I see the DLL code in Visual Studio?

You can easily open a DLL file in Visual Studio the same way you would any other file. To do so, click File in the menu bar at the top, followed by Open. Then click File and select the DLL file you want to open and click Open. This will open the DLL file in a new Resource Editor window.

How do I run a DLL in Visual Studio?

Select the C# or Visual Basic DLL project in Solution Explorer. Select the Properties icon, press Alt+Enter, or right-click and choose Properties. In the Debug tab, select Open Debug launch profiles UI. In the Launch Profiles dialog box, select the Create a new profile icon, and choose Executable.

This is exactly what the Object Browser is for.