Why do you need a job offer to sponsor your spouse/common law partner?
State your previous job, your savings and start looking for a new job.
Explain your plan, and when you get a new job, update IRCC.
Do not misrepresent yourself to "pretend" that you still work for your previous employer.
As long as you can have a plan to support yourself and PA, you are fine. Do not apply for social assistance. (i.e. welfare)