Do i have to be a permanent resident (citizen or green card holder) to get health insurance here? oxford, united, blue cross.. no enough info online

Not necessarily : you need to discuss the specifics with the health plan. The major limitation of obtaining insurance here is being able to afford it. This may be different in different jurisdictions, but I think the final decision will depend on the insurance company. If I you tell you about federal insurance I doubt you can get it

Lawfully present?: Here is a link for you. It will describe the circumstances and documents required to buy health insurance through the Marketplace. Individual insurance companies may have their own requirements. Welsome to the US! https://www.healthcare.gov/immigrants/