As per the OINP Website:
"Under the Canadian Experience Class, you must have:
- at least one year of cumulative paid full-time work experience (or the equivalent in paid part-time work) in Canada in TEER Category 0, 1, 2 or 3 of the NOC"
Source:
Ontario’s Express Entry Human Capital Priorities stream | ontario.ca
Based on what you said, it doesn't seem like you qualify for the HCP stream. It is not unheard of that the OINP send out NOIs to candidates that on further inspection, don't meet the criteria.
You can try and wait for a STEM Draw but those are few and far in between. Also, they barely decrease the CRS cut-off. The last draw cut-off was 481, a 5-point decrease since the previous draw, even after inviting 4,500 more people. Are you at least 3 to 5 points away from that cut-off? If you have the time left in your current temporary status (assuming you are inland) and are close to the cut-off, then waiting can be an option.
Cheers!