Business name change
The literal name of the business is 'English Only'? If you have the business claimed, you can edit your business listing by logging into your GMB account. On the other hand, if you want to add a modifier to let potential customers know that you only have English speaking staff on location (for example: 24/7 plumbing - English Only) then that's a breach in Google's Guidelines:
our name should reflect your business’ real-world name, as used consistently on your storefront, website, stationery, and as known to customers. Accurately representing your business name helps customers find your business online.
You can however use Google posts to get extra information showing along with your business in the Google search results when customers look you up online. Posts only stay live for 7 days, so you'd need to keep reposting, but it's something at least.