You can improve a portrait in Lightroom using 1 of 5 different methods:
1. Use the AI editing feature in Lightroom and choose from the options they offer.
2. Use the portrait presets they have loaded for free under the premium tab.
3. You can make adjustments yourself such as lifting highlights and adjusting vibrancy and clarity.
4. You can download free Lightroom portrait presets from various developers online.
5. You can purchase professional presets for portraits from various developers online.