I do 20-25 mins of cardio (running on treadmill - I am unfit but I’m trying to follow Couch to 5k and I am finding myself able to run for slightly longer periods) then I do two or three weight machines, focussing on arms as I want to tone them. What else do people do? I don’t really have time to do much more than that?
I wouldn't prioritise cardio over weights. And certainly don't do cardio THEN weights.
Think about it over a week: do your C25K 3 days a week, and do some strength & resistance training 3 times a week on different days. Run outside, then you can be efficient re time.
In the gym, I'd be doing HIIT or metcon, rather than steady state cardio.
And a weights programme over 3 days - you could do the really traditional push; pull; legs
So one day do deadlifts or sled pulls or pull ups (pull); another day do overhead press, bench press, or dumbbell thrusters (push); on another do barbell or dumbbell weighted squats, or leg press, or weighted lunges (legs).
Can you add in more walking? Aim to do at least 10,000 steps a day. It's amazing how that boosts your daily energy expenditure - far more than 20 mins on the treadmill.