Fashion Design

Overall INIFD has a little lower rank in terms of studies and placements as compared to other fashion colleges. But saying about specifically INIFD Mumbai campus, it has a little good reputation. As per opportunities, placement level is 50-60%. So, half class is expected to be placed.
That means, in a class of 50 students, 25 are expected to have job opportunities.
If you have time, as in if you are planning for admission in 2018, I would strictly recommend NIFT, Mumbai. Prepare well and get selected and have a 75% chance of getting placed along with the best and updated faculty of country (saying from personal experience). I have a few friends studying in INIFD and they told me that INIFD Ghatkopar provides a lot of job opportunities for their students. They also help you to get in Lakme Fashion Week which is one of the best opportunities a fashion design student could get. They have tie-ups for placement with brands like Tommy Hilfiger, Duravit and Asian Paints etc. A lot of opportunities come your way while studying at INIFD. Check their website for more details - Inifd Mumbai - INIFD Ghatkopar

Visual merchandising is something related to retail industry which helps in boosting sales of a retail store.
As you have completed class 12th in 2016, I assume now you are pursuing some Diploma or graduation. For a visual merchandiser, two things are required; 1) Knowledge of design 2) Knowledge of sales.
You can have these options to enter the retail industry: - completing a retail design qualification at college while looking for work OR moving from an in-store sales assistant role to a trainee visual merchandiser post.
Pursue MBA in marketing and join as an in-store sales manager and then shift to trainee visual merchandiser, this way will help you gain knowledge of sales as well as visual designing. If you go for a course then acquiring sales knowledge will be a little difficult task.
Hope I have added some clarity to your thoughts.