How do I know if my insurance agency is ERISA of 1974 elegible?

Answer 1

I don't understand your question. ERISA is the pension law that was passed in 1974. All employers who adopt a qualified retirement plan that is subject to tax code sections 401, 403 or 457 are subject to ERISA laws. It is not a matter of eligibility this law is mandatory for all such plans.
If your employer offers a 401K plan, a pension or profit sharing plan, or an annuity arrangement they would be subject to ERISA.
All such plans are required to purchase an ERISA bond that protects the plan assets from unethical practices of the plan administrators or the plan trustees.