I am new in here as well. I have been on an extreme diet program for the last 10 months in Thailand. I was a a bit over 190kg (massive) when I started. 10 months later I have dropped 48.6kg. I am 1.4kg away from my next target which is a loss of 50kg.
I started with mild Cardio - Walking - When you are 190kg+ walking is an effort all by its self. I then started gym, under supervision to start with. I did Cardio in the morning then in the afternoon gym then evening cardio again. It was hard. But it got better.
My diet has been adjusted a few times, the gym owner here is an expert, & right now I have been on Keto for the last 5 weeks & I am loosing again.
You will hit brick walls but just dont give up. This is as much mental as is it physical. A good gym will have good people only too willing to help you if you let them. Once they see you are serious & committed the majority of them will help you as much as they can with advice & tips even diet plans if they are good enough with that sort of thing. Here I am lucky. They train world champions in a number of sport so there is a great knowledge base.
Keep me posted on you progress.