Camera Profiles Missing in Lightroom or Adobe Camera Raw
Lightroom 7.3 and Adobe Camera Raw 10.3 has changed the way camera profiles are applied Adobe has changed the camera profile location in updates that launched recently. The Profile Browser is new from the update with Lightroom Classic CC 7.3 and Adobe Camera Raw 10.3. If you open Lightroom Classic CC 7.3 and navigate to the Develop Module on the right hand side of the window you will see the Histogram and directly below that the "Basic" panel. The second option down in these options will show "Profile:" if you either click the drop-down arrows and select Browse or click the 4-small squares to the right of that the "Basic" panel then changes to Profile Browser. Your camera profiles should be listed under the "Profiles" section in the Profile Browser area. You may want to change this option to the List view here which made it easier to navigate by list rather than the grid or large views. Adobe Camera Raw 10.3 will have very similar options in the Basic panel as Lightroom Classic CC 7.3.
Take a look at the following link from Adobe which shows this in better detail: