There is no specific number of words you are expected to know. However, since C2 is the highest level of language competence, your vocabulary range should be very extensive. How long have you been studying the language for and did you recently complete a C1 course? If so, I would recommend the following resources:
For mock exams
fit für c2
For grammar ...
"Paul Smith ist da" is more somebody else would say about Paul. For example, if you arrive at a party and see Paul, you might say to a friend who came with you, "Schau mal, Paul Smith ist auch da" ("Look, Paul Smith is here as well").
A more natural way of introduction in this context would be something like
Ich bin Paul Smith
Diese Redewendung, in der "davon" in "da" und "von" getrennt wird, dürfte aus dem norddeutschen Sprachraum kommen. Ein ähnliches Phänomen ist
Da nicht für
anstelle von "dafür nicht".
Es gibt weitere Beispiele dieser Art:
damit: Da bin ich nicht mit einverstanden. (vgl. Olafants Kommentar)
dagegen: Da bin ...
“Spitzen” here is most likely short for “Zehenspitzen” - which means the tips of (one’s) toes. The following line - which talks about heels and toes - would fit this interpretation.
And the comma isn’t related to the “schön” but rather to the “dass”, which is preceded by a comma because it connects a “Nebensatz” (subordinate clause) to the main clause of the ...