Translation:There is probably wine with lunch.
Think of it as "having wine to lunch"; where we might say we're having something at lunch or with lunch, the Germans say "to". Prepositions never translate well between languages, you just have to expect it and learn the differences.
I find it easiest to think of the word meaning the same thing, but being used differently.
wahrscheinlich = probably
anscheinend = seemingly
vielleicht = perhaps
The most interesting of these is "anscheinend".
It means you have some some reasons to believe things are like that, only you are not quite sure yet.
"There was a clinking of glasses. Anscheinend gibt es Wein zum Essen." (It seems there will be wine for lunch)
The verb must be in second position in a statement, so when you put an adverb in first position es gibt becomes gibt es after you put the verb second and the subject right after it. gibt es can also be used to start a question, since the verb goes in first position in a question like that.