Bonjour, BRAVE for the effort!
You question is interesting as it touches on entrepreneurship, and the path from hobbyist to designer to manufacturer.
Been through it all since 1970s.
Mass production eg 10K pcs needs design and tooling eg PCB fab Gerbers, CAD schematics, and a costed BOM with all suppliers.
That mass production doc package can then be sent out for RFQ to various fab houses.
Beware that ALL Chinese fab can and will steal any design or technology if its in their interest. And that a proto or first run will not represent the quality or parts afterwards.
However, Very sorry but there is no "manufacturing partner" who can industrialize your design for mass production. Nor can they assume any economic risque, you are responsible for the liability, regulatory compliance and so on.
After you create the final design package, and after a quote is received and accepted, they becom JUST a vendor, limited in what they do by contract and PO.
The steps for a good path:
1/ Secure funding
2/ Find a consultant or firm to make the final design with BOM, PCB, assy diagrams, test program, etc.
3/ test and accept design
4/ Issue RFQ to several fab houses.
5/ Select best vendor, issue contracts and PO.
6/ Pay advance for tooling and parts order of 10K
7/ arrange for onsite inspection and QB BEFORE shipping
8/ Arrange for shipping logistic, recieve shipment
9/ Incoming inspection, and accept product
10/ Fulfill orders
Notice ADVANCE payment for parts and tooling is required and that you trust the vendor to fulfil.
Many in that situation off load the process to a Manufacturing expert with Asian liaison experience.
These firms exist in USA and I am sure in Canada.
Bon Chance!
Jon
(just the ramblings of an old retired EE)