Can I get a US job without having a valid work visa?

No, you generally cannot be successful in obtaining a US-based job without having a valid work visa or employment authorization. US employers are legally required to ensure that all employees are authorized to work in the country. Without a visa such as an H-1B, L-1, O-1, or an Employment Authorization Document (EAD), most companies will not be able to hire you. Some employers may sponsor you for a work visa, but you must secure that sponsorship before starting the job.