This is such a frequently asked question. Most people assume that the winery has added some flavor extracts to achieve those flavors. Though there are some inexpensive wines that do add fruit flavors, these wines are called formula wines and the extra ingredients are listed on the label. Those are more like wine cocktails in the bottle.
Most wines are made from specific grapes – period. The natural fermentation brings out the natural flavors of the grape which are reminiscent of other fruit flavors. These fruit flavors vary based on the grape variety. For instance, Muscat Canelli is prized for its peach and apricot nectar flavors. Rieslings are famous for apple characteristics. Red wines list blackberry, blueberry, strawberry, etc.
These flavors come from the chemistry of the grape. The natural chemical combinations in the grape give it flavors that remind us of other fruit flavors. For instance, you may taste a wine that reminds you of your grandmothers fresh apple pie because the grape has apple characteristics. The fun in the tasting of the wines is identifying those flavors and the memories they illuminate.