Hello student Haryana open School (HOS) is a valid recognized board and yes certificate from HOS is valid for B.tech. You can surely secure job in top MNCs like Google, Amazon, TCS etc on the basis of your academic performance and skills throughout your course.

I request you to please help me with the college in which you're willing to pursue B.tech so that I can check and provide you with the exact information about eligibility criteria and admission process.

For more details refer to the link mentioned below - https://www.google.com/url?sa=t&source=web&rct=j&url=https://bseh.org.in/haryana-open-school&ved=2ahUKEwjS4vzfhaXtAhUbyDgGHa5HARkQFjAAegQIAxAC&usg=AOvVaw0vLuR5Tveg-YjTqs15tDfG

Feel free to comment if you've any doubt

Good luck