In Lesson 10, it says, "strings are sequences of characters, like the letters a-z, spaces, and even numbers." This makes it seem as though only "even numbers", as opposed to odd numbers, can be strings.
That is not what even means in this case. Beside, would it make sense in the sentence? Guess not, even has another meaning here, for example:
even george is coming is to the party
Even has the same meaning in the exercise as the sentence above. I as non-native speaker understand this, so should be fine
I realize that, but it's unnecessarily confusing to complete beginners who aren't familiar enough with a programming context to know that "even [i.e. not odd] numbers" wouldn't make sense. In your example, "even George" cannot possibly have the other meaning (not odd). But "even numbers" is a perfectly valid group of characters. It turns out that it's an irrelevant grouping here, but it's not nonsensical.
Plus, usually when you use "even" as an adverb, you usually end with an exclamation point. For example, "George has eaten lots of different foods—haggis, shark, and even cockroaches!"
if you post you code i might be able to help, but if not, try this code:
"Write what you want here".length