So sorry, looney tunes, I can't be sure of the amount of topsoil you purchased because I don't know the size of the area or what is presently there.
Call your local [url=https://extension.unh.edu/Counties/Counties.htm]cooperative extension service[/url] (provided Manchester is in New Hampshire. Or is it a different country?) for help on that. See if you can get someone to come out and examine the area and determine how thick the topsoil should be (between 3-6 inches), which will determine if you bought enough. They can also help you with a soil test, as purchased topsoil is not structurally adequate to sustain a lawn in most cases. Most often, you will need to mix in some sand, silt, clay, and/or organic matter like compost.
Extension services are very helpful to home gardeners and it is what they are there for. However, if you are unable to get someone to visit to inspect your yard, then ask at a local garden center. You really need to know about the soil and sub soil condition and whether you need to add any soil components to the topsoil you bought.
For the most part, all you need to do is spread the soil then level it out. Rolling should not be necessary. I can tell though, the lawn will not be ready for traffic this summer. After it establishes, baby the grass for a year and stay off it.