Best to get checked out at a good running shop, or by a physio.
The received wisdom is that overweight people tend to overpronate quite a lot, and need high stability shoes... with good cushioning. But these are nothing outside the normal range of shoes... some "average" weight runners will also need these.
If you do lose a lot of weight (which will take control of diet too), any overpronation might naturally reduce... so get checked again.
Well done, good luck and have fun.