You don’t need a lab coat to stop ants. White vinegar is the superhero you already own. Mix one part vinegar with one part water in a spray bottle. Spray it along their trail and around doorways.
Ants hate the smell. It destroys the invisible scent trail they use to navigate. When you wipe that trail, they get lost. They wander around looking for the party, and eventually, they give up and go home. It’s not toxic, it smells like a salad dressing, and it actually works.
Another cheap trick? Cinnamon. Sprinkle a line of ground cinnamon on your windowsill or near a door. Ants will treat it like a moat. They refuse to cross it. It’s like having a tiny, spicy barrier guard.