To view and edit your photos in Lightroom Classic, your first step after opening a Lightroom catalog must be importing your photos into the catalog from the Library module.

How to import your photos/folders into the catalog

There are several methods of importing photos. First, Make sure you are on the Library module.

1. Drag and drop.
   Drag the photos or folder containing the photos into Lightroom until you see the icon marked in the screenshot.
   
   
   
2. Add a Folder.
   Left Folders Panel -> Click on the "+" icon -> "Add Folder".
   Browse and select the folder containing the images.
   
   
   
3. the "Import" button will open the Import dialog box (keyboard shortcut Cmnd+Shift+I (Mac) / Ctrl+Shift+I (Windows))
   
   a) Select your relevant folder from the left "Source" panel.
   b) All the photos located inside the chosen folder will be selected automatically.
   If you want to import only specific photos inside the selected folder, uncheck the box as seen in the screenshot.
   Unchecking the box while multiple photos are selected will uncheck all selected photos.

   

   c) After your selection is final, click the "Import" button on the bottom right to begin the import process.

Additional import settings worth knowing

1. "File Handling" setting.
   • "Build Previews" Choose the photo preview size.
     If you select a preview other than "minimal",  Lightroom will automatically initiate preview creation after the import process finishes.
     if you import the images just to get them into Imagen, and no reviewing is needed, leaving the "minimal" option is recommended. 
   • "Build Smart Previews" Takes additional time after the import process finishes, and it's not required to build them, though it's recommended to do so as it makes the upload to Imagen more efficient.
2. "Apply During Import" setting.
   • "Develop Settings" Choose a preset to apply to all photos on import.
     The recommended setting when working with Imagen is "None".