i want become software engineer in the IT ? which subject i need study and which programming language is best in the IT field?

If you plan to learn only one or two languages ever you are missing the point. So any language is good at this point, even Scratch.
Look at both object oriented languages (like Java) and more machine close language (like c or c++)
GLHF!

Hi ,

Most software engineer positions require a bachelor's degree.[1] Majoring in software engineering will provide the most useful background for designing and perfecting software in the corporate world.

Even if you're still in school, you can give yourself a huge head start by teaching yourself programming. Software engineering is not focused exclusively on coding, but you will need to know at least a couple languages, and a deeper understanding of how they function. There is no widespread agreement on which languages are most useful, but these are all popular choices:
C++
C#
Java
Java Script
Python

Java, Python, C++ are trending object oriented language's. You can also check free video on these languages in udemy.com website as well

Step 1: Learn About the Career
Since computer software engineering includes a variety of tasks and job descriptions, the first step aspiring software engineers may need to do is to research the field before pursuing education and training that will prepare them for a particular career path. The types of software that computer software engineers create, test, and evaluate include business applications, network control systems, operating systems, databases, middleware, and computer games. Software engineers may use a variety of programming languages.

Those who work primarily with computer systems may design and implement data assurance and system security, as well as customize computer systems to meet the needs of clients. They may also set up intranets, which are networks that allow different computers within an organization to communicate.

Step 2: Earn a Bachelor's Degree
As the minimum education requirement for computer software engineering jobs is usually a bachelor's degree, the next step is to complete your degree program. Those who work with applications typically major in software engineering, computer science, or mathematics. Courses in a computer science undergraduate program may include computer fundamentals, data structures, principles of programming languages, software engineering, and computer architecture.

Success Tip:

Participate in an internship! Employers may prefer to hire those who have relevant experience in addition to a bachelor's degree. Students can participate in internships during their undergraduate education to enhance their employment prospects. Internships also enable students to gain hands-on experience and learn new skills from professionals in the industry.

Step 3: Gain Related Experience and Skills
Since computer software engineers design new software programs, they should have a high degree of creativity. They should also have strong problem-solving, mathematical, and analytical skills, as well as the ability to work with abstract concepts. Communication skills are also important since they must interact with hardware engineers, industrial designers, manufacturing operations personnel, and end users to develop software products. An entry-level position, such as a computer support specialist or computer technician, can help prospective engineers develop these skills and obtain hands-on experience in the field.

Success Tips:

Before you start on your path to become a computer software engineer, consider 3 more tips for success:

Gain professional certification. Obtaining certification can demonstrate a certain level of competence and make job applicants more competitive. Product vendors, software firms, and professional computing societies, such as the Institute for Certification of Computer Professionals (ICCP), offer certification programs. Those who seek certification from a product vendor or software firm may be required to work with the company's products, while certification from a professional computing society typically requires a series of examinations, maintenance of membership, and periodic recertification.

Continue education and training. Since technology is constantly changing, the job tasks performed by computer software engineers change often as well. Employers, colleges and universities, private training institutions, software vendors, and professional computing societies offer continuing education and professional development seminars to help computer software engineers learn the skills necessary to keep up with changing technology.

Consider a master's degree. Some employers look for prospective software engineers who have a master's degree. Programs like the Master of Science in Computer Science are available on-campus and online.