Step 1: Download your purchase and depending on how you have your browser set to handle downloads, it will either be in a .zip or just the folder itself.
Step 2: Launch Adobe Lightroom Classic
Step 3: With the Develop Panel active, go to File>Import Develop Profiles and Presets and select the The Archetype Process (Kodak Pro, Fujifilm Pro, Monochrome).zip file you are installing or if it is already unzipped, open the folder and select all the profiles.
Step 4: Once installed, the profiles will be available in the Develop Module at the top of the Basic Panel right below, “Treatment.”
Step 5: When installing in Lightroom Classic, profiles are automatically installed in Lightroom and Adobe Camera Raw as well.