This is not a question with any real answer, except that you learn to use the language, and then you learn to solve the problems such a task would pose. That does not mean that MATLAB would necessarily be a good tool for such a task.
To solve a large task like this, you would need to break it down into smaller problems. Thus, first learn how to build a searchable database that would contain images, and a list of keywords associated with each image. You would also need to build a dictionary for each keyword, this time with a definition for each such word.
You would best build the above tools separately, with no gui interface, just as a function call. This allows you to test out and fully debug the separate parts of the system.
Then you would need to spend some effort to build (or find) the necessary databases.
Finally, you design a gui interface, one that would be capable of calling the tools you have written. This means you need to learn to work with the necessary tools.
Again, break the problem down into manageable sub-problems. Learn to solve each sub-problem. In this case, you would need to learn about databases, about searches, about graphical user interfaces, and about how to package things into an app.
Is MATLAB the best tool for such a project? Probably not, since MATLAB is designed more for numerical work, nor does this mean that MATLAB would be inappropriate for the task. But the problem would be completely solvable in MATLAB. And in reality, the best tool for something like this is the language that you understand well enough to be able to solve the task at hand. That would surely be a different choice for different programmers.
