Open Blender, go to "Edit" > "Preferences" > "Add-ons". Click the "Install" button, then navigate to and select your add-on file. Search for and enable the add-on you just installed. Installing ...

If you are having trouble importing a .rdc file with this add-on, please provide the following information: The .rdc file (it wont let me upload the file) Nvidia GeForceRTX 3080 Ti Map Models Importer ...