Meaning of "Shares per lot"

Hi there,

I just start in this world of trading, and I am trying to understand as better as I can. However, for me it is not clear the meaning of “shares per lot”. For example, if I want to trade CFD and it is wrote “100 shares per 1 Lot NYSE”, what does this means? How can I know the lowest price I need to buy?

Thank you for your help.