Before installing the plugin you need to be sure about the PHP version that your WordPress is using.
From the download page of the plugin you will find which PHP you are going to need.
If you’re running WordPress 5.0 or higher then you can simply check the PHP version on the WordPress website. Just login to your Admin Dashboard then click on Tools > Site Health.
Now you’re on the Site Health page. There are two options Status and Info. Just click on ‘Info’
Now click on Server there you will find a section called PHP Version.
If you need to update your PHP version you should ask your hosting provider. Different providers have different ways for doing it.