Primary NOC must be noc type 0, A or B.
For foreign work experience Primary NOC must be at least
1 year of continuous paid work or 1,560 hours total (30 hours per week) or equal amount in part-time.
https://www.canada.ca/en/immigration-refugees-citizenship/services/immigrate-canada/express-entry/eligibility/federal-skilled-workers.html
For Canadian work experience Primary NOC, you must have at least
1 year of paid skilled work experience in Canada, in the
last 3 years before you apply. It must be full time (30 hours per week) or equal amount in part-time. It doesn't have to be continuous. Work experience during full time study does not count.
https://www.canada.ca/en/immigration-refugees-citizenship/services/immigrate-canada/express-entry/eligibility/canadian-experience-class.html
You can select your either experiences as primary NOC if you meet the above condition and can provide reference letter from your employer which meets IRCC requirements. If you fail to meet IRCC requirements in your work reference letter then you will be dragged to "review required" queue which may take up to a year to finalize your application. here is the IRCC specification for work experience letter. The official link provided below should be used to prepare all mandatory documents as well.
The following documents are mandatory for each work experience declared:
- a reference or experience letter from the employer, which
- should be an official document printed on company letterhead (must include the applicant’s name, the company’s contact information [address, telephone number and email address], and the name, title and signature of the immediate supervisor or personnel officer at the company),
- should indicate all positions held while employed at the company and must include the following details: job title, duties and responsibilities, job status (if current job), dates worked for the company, number of work hours per week and annual salary plus benefits; and
- if the applicant is self-employed, articles of incorporation or other evidence of business ownership, evidence of self-employment income and documentation from third-party individuals indicating the service provided along with payment details (self-declared main duties or affidavits are not acceptable proof of self-employed work experience).
If the work experience is in Canada, proof may include copies of T4 tax information slips and notices of assessment issued by the Canada Revenue Agency (the time period for these documents should reflect the work experience timeframe [e.g., work experience from 2006 to 2008 requires only documents from those calendar years]).
https://www.canada.ca/en/immigration-refugees-citizenship/corporate/publications-manuals/operational-bulletins-manuals/permanent-residence/express-entry/applications-received-on-after-january-1-2016-completeness-check.html
Good Luck!
