You can work on your form to make sure you’re running efficiently. The more efficient you’re running, the easier it will be (and you then speed up). For instance if you’re a heel striker, you can start switching to a more forward-striking gait. (https://fl.milesplit.com/articles/112223/most-read-article-of-2017-heels-or-toes-what-is-the-best-way-to-run)

You can also work in leg training like squats, Romanian deadlifts, calf raises, hamstring curls, leg extensions.

Finally, wind sprints, or running faster (using good form). You should try and get used to what running faster feels like. Even running at a slight decline will help you speed up so you can get used to what the road, wind, cadence all feel like.