Haha, I found this genuinely funny. It’s called an internal monologue. Google tells me that it’s the majority position with 30 to 50 percent not having one.

Personally, I find it very difficult to understand how people could not think in words, like you were speaking to another person. Obviously you also have mental imagery and sound etc, so not everything is just words. Internal speech is one channel of thought, but for anything complex I would have thought it was mandatory.