It depends on the requirements of an IT firm. Few organizations require a Bachelor’s Degree of either 3-4 years. Whereas, some tech giants like Google, Microsoft, etc., don’t need any degree as they primarily focus on an aspirant’s talent and skill set.
Consequently, it usually takes 3-4 years to become a Full Stack Developer after the 12th standard as the majority of firms require a Bachelor’s Degree in either Computer Science or Information Technology. However, an aspirant can instantly become a Full Stack Developer at a beginner’s level by cracking the jobs in tech giants like Google or Microsoft. But the aspirant must have immense expertise in programming languages or implement any software-related projects.