To merge multiple projects into a single project, the user can right-click on the project(s) data and select "Copy Object(s)":

Then choose the project that you want to move the data to, and then select "Paste Data Object(s)":

You will then be prompted to select the objects to paste, and whether to clear the clipboard after pasting the object:

Upon selecting "OK", the data objects will be pasted to the desired project.