What are the most effective weight loss exercises while working out at the gym?

Ive been loosing weight over the past few months. Now that I have a gym membership I was wondering what workouts are most efficient at weight loss. I go about 4 times a week. Thanks

any type of cardio i.e. bike, treadmill, eliptical.

Weights would also be a great addition.

A lot of gyms will allow you to have a personal trainer for free the first couple times. I’d look into that.