Python is the compulsory language to learn to become a data scientist but you should also be familiar with the R programming, SQL, NoSQL, and SAS. The compulsory language for Data scientists is Python because it has an abundance of libraries for data analysis, data modeling, computer vision, and natural language processing applications. After that, learn SQL and NoSQL for storing and retrieving the data from relational and non-relational data from the databases. SAS (Statistical Analysis Software) has the same features as Python and R, mostly used in the banking sector.
Also, watch this video on Data Science: