It typically takes wine just about a week or two to ferment, usually between 10 and 15 days. However, this may vary by technique and recipe; some wines take more like a month to ferment. Fermentation is also not the final step in winemaking.
After grape juice successfully and fully ferments, it is not yet necessarily ready to be consumed as a fully fledged wine. Some wines, particularly red wines, need additional time for processes such as aging. White wine typically requires less aging time than red wine because red wine's flavor tends to develop nicely over time, which may not be the case with all whites.