Whilst heartburn and wind can happen at the same time, especially after a big meal, they’re usually separate problems that need to be treated separately.
Gaviscon works specifically to relieve the symptoms of heartburn and indigestion, so probably won’t help with excess gas.
If you’re feeling gassy, the best medicine to try is simeticone, which works by bringing together the small gas bubbles in your gut to form bigger bubbles that can pass through your body more easily.