I am putting a bathroom in the basement and I need to know how to set up the underfloor piping. The toilet will be first then the shower, sink and the ejector pit.

Thank you in advance for any help you may have

Will a permit be pulled and will it be inspected? Are wet vents allowed in your area? You do know that while the fixtures may be revented back to a dry vent the ejector pit vent MUST be a dedicated vent. It can't be tied back to the house venting. It must be a single vent coming from the pit and exiting the house by itself.
The reason for this is that while then pit pulls air into it as it pumps out and discharges like a regular vent, it expels sewer gas as the fixtures discharge into it and nobody. Least of all the plumbing inspector, wants pressurized sewer gas into the house vents. Let me know about the wet vent and I'll send you a layout that only uses one vent for all three fixtures. Back to you, Tom