Hi Kailee and welcome to Scibuddies!
Herbal remedies are important in many societies even today. The area is huge, however and you need to narrow it way down to do a science project in a reasonable time with high school resources.
The problem is not about finding herbs to test because there are hundreds to choose from. The difficulty comes when you try to choose a method for testing them. You can't test them on your friends as school projects don't allow that, so you need to use some organism as a stand-in.
Here is one common type of test that uses a harmless culture of E coli bacteria:
https://www.sciencebuddies.org/science- ... on#summary
This project tests the antibacterial properties of antiseptics and mouthwashes, but you can use the same method to test herbal preparations and extracts.
You could simply do a search for 'science projects herbs' and see what you find online.
Herbs are most often thought of in terms of preventing or curing diseases in people, but they can also be useful in gardening to keep pests away from vegetables and flowers. Strong smelling herbs like mints, rosemary and basil can keep certain insects like bean beetles away from food plants simply by being grown near them. Herbal extracts can also be sprayed on plants to act as repellents (
https://food.ndtv.com/food-drinks/5-nat ... en-1877271).
There are many other possibilities for an herb-based science project, so think about this some more and then get back to me with your questions. I can help you choose a great project and make it work!
Good luck,
Sybee