I just joined a new gym on the march 1st too. Went and worked out 3 times last week and I'm already feeling better. First day I spent about 45mins just getting my cardio up.
2nd I went 30 mins on Cardio/30 on the weights
and the last one I went 20 mins on the cardio and 40 on the weights.
This week I'ma just do two days of cardio and 3 days of lifting.
I'm focusing a lil more on toning up then losing weight.
There is a gym sub forum to help you with a workout routine, but my only tip is make sure you adjust your diet too. If you got eat bad and workout you gonna slow down your progress.
Good luck bruh