@simisim it sounds like your host might have some restrictions on new files (perhaps storage limits). Reaching out to them is a good step.
As for Local, you can use it with any host, but you would need to “SFTP” your site to/from your host to your computer or use a migration plugin like https://www.ads-software.com/plugins/all-in-one-wp-migration/.
My suggestion for a local environment was more around trouble-shooting (e.g. could you install the plugin locally vs. your host). Reaching out to the host will likely help you isolate the problem with installing the plugin without having to do a local test.
You may also want to ask your host about any “staging” options they have for your site. It’s best to install and run new plugins / upgrade PHP in a test copy of your site first and not on your live site. Your host could have a free staging option for you, or again, use something like LocalWP to test locally on your computer.
The other important thing to consider about Local / staging sites, is that they let you select your PHP version when testing your site. This means, that you could select the current versions of PHP to test on a copy of your site without having to do that on your live environment. For Local, select “custom” when setting up a new site and you can select the most current version of PHP.
As an FYI, this plugin is a “linting” tool which basically will tell you which parts of the code of your website *might* be problematic in later versions of PHP. While it’s a handy tool, again, it’s best to test a copy of your site in a staging or local environment before you make PHP version changes on your live site. The plugin will help you figure out what to watch out for, but you’ll still want to make sure the pages look right, your forms still work, etc.
In any case, good luck. depending on what version of PHP you’re upgrading from, you’ll likely have a much FASTER website waiting for you at the end of this project ??
