Liliann- just take things slow, one meal at a time. Try to think about what you are eating and why you are eating it. So often we put food into our mouths that we hardly taste, just to salve a need. Look at your portions and think about whether you need to eat everything on your plate. There's no need to count at this stage, just try to cut out some of the processed carbs, and add in more veg.
As for the exercise go ahead and join the fitness center if you think you will go. At the beginning of my journey there's no way I'd have gone. I bought a static bike and rode it whilst watching TV. I could ride 40kms a day
Do little things Liliann. Yours will be a long journey, but as with all journeys, it starts with the first step. I eagerly await news of your great success. Feel free to PM me if you wish to chat