Have you got an answer for this question yet? I don't reside in Ontario anymore, but what I know is, if this hasn't changed, when you apply for the OHIP (I am not sure if non citizens and PRs would be able to extend it without proving you are currently working), you need to meet the criteria, things like working full time, having the employer write a letter, etc. Service Canada would provide you with a list of requirements (this is the part that I'm not certain about anymore; perhaps the rules have been altered during the pandemic). Hope this information helps.