You can do B.Ed after a gap. There is no issue. You can do B.Ed by correspondence course. If you secured 50% marks in your graduation you can apply for B.Ed. Are you a Post Graduate or Graduate. This is not clear in your question. Anyhow, you can do B.Ed course which is a two-year course.
As an Engineer in biomedical engineering, you have many options for jobs.
Manufacturing Engineer: They will develop and design medical products. These products may include medical instruments, imaging devices, etc.
Quality Engineer: Quality engineers test medical products after they are manufactured and confirm that they meet the prescribed specifications.
Software Engineer: They do the design and development of computer programs which are useful for various medical applications.
Researcher: Many researchers also teach at the university level. They will work in the research organisation and do the research related to the field.
You can try any of these jobs also.
If you are PG, you can think of appearing for NET examinations and once you are qualified in that you will become eligible for lecturership or you can also try for PhD.
In addition to all the above, you can appear for bank examinations, State government jobs and central government jobs. For all these posts you are eligible and you can apply for these posts when there are advertisements for these posts.