Email replies received in computer language-HTML

Of late the language to some responses to my emails have been in HTML and others in English. Some of the responses have been from Microsoft and when I questioned how I convert the emails to English they answered and you've guessed it was HTML. Despite extensive searches of the Internet I have still not been able to find an answer to the question "how do I convert emails received in HTML to English. Can anyone help me?

If I am understanding your need you want to do 2 things...convert html email to text and then to translate that text to English. Correct me if I am wrong.
I do not know what email app handles your email but most I've seen have an option you can set to have the replies to your emails in the same format as your sent email. If this option is set, then your selected computer language should then show the email in your own language. It might help me give a better answer if you would provide more information regarding your email app.

As far as both converting and translating into another language at the same time, I know of no app that can do both but there are online converters and translators you can use to perform the functions one at a time.

1. first convert html to text using one of these methods
Method 1- use an online converter. There are many available.
HTML to Text Email Converter | Email Design Reference
Method 2 Use notepad to convert html to text
How to Convert an HTML Document to a Text Document

2. then use the language translator of your choice to convert the text English or any language. There is a translator built into Windows. It should be in your list of apps. I prefer google translate myself.
google translator - Google Search

Would Yahoo be the email account which have HTML/gobbledegook emails? If yes then it’s a known bug with MS & Yahoo email accounts, so far there’s no fix.