This section will demonstrate how to place Actors from the Content Browser in your level through a Context Menu.
Inside your project, in the lower left corner of the screen you will see the Content Browser.
Locate the asset you wish to place, this could be: Blueprints, Static Meshes, Particle Effects, Sound Cues, Skeletal Meshes, etc.
Left-click on the asset so that it is highlighted.
Inside the Level Viewport, Right-click anywhere to bring up the Context Menu and select the asset under the Place Actor section.
After selecting the asset from the Context Menu, you will see it appear inside your level.
You also have the option of adding a different type of asset even when you have a specific asset selected in the Content Browser. You can see the types of assets you can add by opening the flyout menu in the Add Actor section of the Context Menu as seen in the image below.
If you have one or more Actors selected in the Viewport, and an asset selected in the Content Browser, you can opt to replace the selected Actors in the level with the selected asset by clicking the asset's name in the Replace Selected Actors with section of the Context Menu as seen in the image below. This may be useful if you want to do sweeping changes and swapping multiple assets out at once.