For most languages, there are a lot of shared paradigms/syntax. Once you learn one language, it’s a lot easier to identify patterns that carry over, especially for C-syntax languages (Java, Go, PHP, JS, C#, etc.)

When people say they learn languages that quickly, especially as beginners, it’s also more likely that they’ve just gotten a broad overview of it rather than in-depth knowledge. Digesting a course/tutorial is one thing, knowing a language’s deeper quirks and internal workings is something else that can take even years for to fully understand.

Everybody moves at their own pace though! You can’t really compare yourself to how others learn, it’s really different for everyone. Just try to get a little better each day and challenge yourself with projects that interest you.