Answer 1

Hey Shrikant! I'm not sure if I got the question right. It depends on what exactly you want to do with your DB and what platform, datamodel etc you want to use. But it won't be a mistake to start with SQL on sololearn. You can then have a look at DBMS like Postgres, pgAdmin or others. There are plenty. Later you might need php for web development, depending of the purpose of your project.