How can I get rid of insects that are eating my plant leaves?

Are your plants inside or outside?

What kind of plants are they?

Mist with peppermint oil then sprinkle with cayenne pepper powder, reapply as needed.

For the best local professional advice-

I would highly suggest contacting your cooperative extension. These offices are manned by volunteer master gardeners on site there waiting to answer the communities questions that know your local situation quite well.

Bringing in the foliage and insect will provide them with the tools to id the pest and suggest proper treatment from their pmg guide.

Master gardeners are required to volunteer back designated hours ( plus continuing education) each year to maintain MG certification -this community outreach and education is their goal.

Here are some different ideas that will help: https://www.angieslist.com/articles/insects-bugging-your-plants-try-these-10-natural-insecticides.htm