Seeing how Real Madrid won over Barca in the copa del rey even though they are quite doubtful to be able to do this, will make Real Madrid's confidence even higher and Chelsea, who are the opponents, will find it difficult to withstand the onslaught Madrid in the first leg, my prediction will be a match where Chelsea will concede quite a lot of goals from Madrid without them being able to reply to any of it.
Chelsea is a club with quite a lot of expensive players in the transfer market but they don't have good coordination with each other, that's why any team always has a chance to beat them as well as Madrid.
Benzema will be very comfortable scoring in this first leg and a new record for him will be possible.
Chelsea will obviously struggle against Madrid. even the results of the last 3 matches of Chelsea are also not good. Chelsea's last 3 matches without a win. if Chelsea can hold Madrid to a draw in the first leg, it is a miracle that no one can predict.
it is not impossible that Chelsea can play well later. but their team's current condition is not good to face a team as strong as Madrid. maybe Madrid will indeed get a lot of goals, Benzema could be a beast again.