Functions embedded in Julia

I installed Julia on a laptop running ferdora 36 operating system. I tried to capture some xeta function values but the answer was that zeta(x) was not recognize a a valid command. I read on the Julia manual that zeta is embedded in language. Does anybody know why this happened to me?
Thanks a lot in advance

I think you need

using SpecialFunctions


OK thanks. I’m very new to Julia, and I learn just now that I need additional packages.
Thanks a lot and sorry