Ants in the lawn are a nuisance, but can be beneficial.  They help aerate the soil.  The ant activity may resolve on its own if you give it some time.  If you do decide that they need to go, there are a few non-chemical things you can try.  Disturbing the nest with a shovel may cause the colony to seek greener pastures.  Diatomaceous earth often works well on small ants. Pouring a tea kettle of boiling water on the nest can be effective, too.  There are chemical controls that can be used.  If you use a chemical, be sure to read all of the instructions and warnings and follow them closely.   I am attaching a fact sheet that covers various aspects of ants in lawns.  https://yardandgarden.extension.iastate.edu/how-to/how-manage-ant-mounds-lawns-gardens-and-pastures  

Once the ants are under control, you should be able to reseed as you would a normal bare spot.