Do you have to be fluent in English to be a Programmer?

No, you don't have to, but it definitely helps. If there is no documentation and knowledge sharing in your own language, then you will be constrained to the most basic level of programing. You can't find, invent, or deduce everything that thousands others have created and deployed for decades. Countries like Russia and China have big enough communities that they can maintain knowledge base that is sufficiently large to serve most of the needs of their communities, but even then knowing english helps to not reinvent the wheel at any single step.

Important to note there are two 'flavours' [with a fecking U!] of English. So, even if you're a native English speaker, it can be almost as frustrating, as most programming languages are written in US English. So, if you're the kind of person who takes a pride in your spelling and grammar, there's the constant thorn in the brain of having to deliberately spell words wrongly all the time, such as needing to write:

color instead of colour

center --------> centre

math ----------> maths

And then these new-fangled languages [like Crystal] come along and add to the misery with their:

fiber ---------> fibre

I'd say "no", or at least "not particularly". Obviously there are careers that require even less knowledge of English, for example in music (I knew someone who chose to study music specifically because they didn't know which country they might end up in), but many careers require more knowledge of English than programming, so if you don't like or are not good at (human) languages then programming is not a bad choice, I think.

That was a very nasty comment. Whoever said it to you, probably wasn't multilingual.

I have worked on a large system for a multi-national drug manufacturer. Some modules were written by Spanish speakers, others by Germans, a few by French and about half by English speakers. It worked well. The only real problem was that variables and function names were all in their respective native languages. At least the module names were all in English (well sort of). I ended up maintaining it because I spoke all those languages (badly) and was willing to use various dictionaries. It was an experience!

In my experience the vast majority of books and internet resources are in English as are the keywords in most programming languages. If you can read English at high school level you should be Ok.

Since programming relies on teamwork, you need to speak the local language well wherever you live and work.

I was told I need to be good a math to be a programmer. Turns out they were totally wrong. Don’t listen to people that say you need x to be y. Most of the time, it’s just someone’s bias opinion.

No you do not have to be fluent. Reading English is more important than writing English, writing English s more important than speaking English.

You will most likely need to read some technical information in English.

You will probably need to write a question in English to solicit help.

You might find a job working with others who do not speak your language.

Having said that, I have seen where English is considered a 'Common' language. The tourism industry seems to have this requirement.

I know a couple, one person is German and the other is French. They live in France. Neither spoke (past tense as they do more so now) the other language. At a party someone asked how they communicated with each other. "English" of course, the common language. The German is able to work in France because of her ability to speak English enables her to communicate with co-workers.