Hi Abir
For getting job as app developer or software developer you have to have skill The minimum qualifications of getting kind of job in this field
1) Bsc in information technology
2) Bachelor of computer application
3) B.Tech in computer science /information technology These are minimum qualifications are required to get job as software developer and application developer
I am giving  brief answer what we have learn to became software developer
1) First you have learn one or two programming language like C++ or phyton there many programming language you can which is more easier to understand
2) After that  go with data structures and algorithm it is key to get job as software developer
3) Application developer you have to learn Java and kotlin programming language after you have to my SQL and server side programming language like phyton php and more after do some project .
Hope it will help out!
Good luck