Gym Exercise Equipment

I started this thing where I have to do cardio four times a week for 20 minutes. I have three opportunities to do cardio for the rest of the week. I need to do cardio this evening, but I cannot go for a jog or ride my bike outside because it is raining (my parents wouldn’t allow me to) and I cannot go to a gym or fitness center right this moment. I also do not have any fancy equipment at my home.
What can I do for cardio?
I know it might sound stupid, but would jogging in place for 20 minutes work?

I recently got a gym membership, but use of a trainer costs an arm and a leg. So I dont really know what I’m doing.

I’m paying for use of all this fancy equipment, but I only ever end up doing cardio and then maybe trying out one or two other machines.

I’m looking for a website that can tell me which machines I should use, how often, and for how long. Something geared towards women prefrably.

thanks.