Difference between baking a cake in cooking range and microwave oven I don't know much about the difference between cooking range and oven. But I just want to know what difference must be made to bake a cake using a cooking range. 
I used to bake cakes in a microwave oven in micro+convection mode at 200 degree celsius. For that I preheat the oven at 200 degree for 15 minutes and then place the cake batter in the oven for another 15 minutes. And that cake used to come out really good. 
But now I am using an electric cooking range that uses a gas cylinder. It has a knob to adjust the temperature and an option to grill. And inside it has holders at three different heights to place the tray. I don't know the exact word to describe my cooking system. Anyway all I want to know is what should be done to make the exact cake recipe which I tried in micro+convection mode at 200 degree?For what duration should I bake and at which height should I place the tray?
A range (also knows as cooker in some places) is a free-standing kitchen appliance with a cooktop (hob) on the top and an oven below. The oven sounds like a conventional gas oven and not a fan assisted (convection) oven. An oven will give you much better cakes than a microwave, you just need to get used to how your oven cooks. 

Most recipes are written to be used in an oven and not a microwave convection oven, so for cooking times and temperatures you should simply go back to the recipe temperature and time for a guide. If the recipe is not available then you will need to do some trial and error. 200C seems a bit high to me, you could end up burning the outside and having the inside overdone. Many cakes are baked between 160 to 180C depending on the type and thickness, so for a conventional (non-fan) oven I would split that down the middle and go for 170C, (155 for a fan oven) and up the cooking time to 20-30 minutes. Try the middle rack your first time cooking in the oven. 

One thing I would recommend is getting an oven thermometer. Many ovens, especially older ones, do not cook at the temperature you set, and can be much hotter or colder than you want leading to bad results. An oven thermometer will tell you how hot your oven actually is inside so you can set it properly.