Hey my bros, fat cannot convert into muscle, or vice-versa. It's physiologically IMPOSSIBLE. Fat (adipose) and muscle are two different tissues. It's the same as how coal can't turn into gold. Coal is coal, gold is gold. This is the same concept with muscle and fat.
Another cool fact: fat cells can grow or shrink in size, but the number of fat cells stay the same. Researchers concluded that the fat cells didn't last forever, but died and were replaced by new fat cells at the same rate, resulting in a stable number of fat cells. (Webmd)
When you are weight training, you can both build muscle and cause fat loss, but they are two separate results from lifting. You're gonna see a lot of articles that shout in obnoxious print, "turn fat into muscle!" It doesn't really work like that. But hey -- I guess it's great for marketing.