Get your taxes done using TurboTax

Oh boy, I just went down rabbit hole and got myself all sorts of confused.  First, do they only tax the amount that is paid out directly to you?  Say for instance, there were times I added $10 to my account, played and was up to $30 and thought I'd be able to win more so continued playing but eventually lost it all.  That is not counted in my winnings is it, if I was never paid that amount? 

I may be misunderstanding, but I read a response to another question on here that "For online sport betting, it would be the same as the person that puts a card in the slot machine (and wins $1000 at a time, its reported). If the bets are all made from the same account, they will summarize for the year."  I wonder if that would be the same for a casino app (slot games) where I have an account with them.  I don't win large amounts at a time, but over time I have.