You can take a look at the MIT license website which has the placeholders.

Fun fact: On GitHub, if you add a file in the web UI and include "LICENSE" in the file name, it gives you a button to choose a license template. Then you can see common license options and a summary of what they do. It also allows you to fill in details like the year and copyright holder.

I'm also not a lawyer, but including both license files and adding to your README that your project is dual-licensed under both licenses at the user's choice should be sufficient. GitHub should also detect both licenses and show them in the project's side bar.

If you copy-pasted the licenses, just make sure to adapt the MIT license, as it includes the year and name of the copyright holder. You should adapt these to your project.