Parameter variables

Part of the DB I am working on contains a table for Emergency Response
data. The primary key ([ERptNo]) is formatted as "yymmddhhmm_ _ _", the last
3 digits being the first 3 letters of the responders last name. If they were
the Incident Commander, additional information is collected & added to the IC
table, with a primary key ([ERNo]) of "yymmddhhmm". I've built a query with
fields from these tables, and need to find a way to add parameters for a
search which would open a report. I would like the IC report to show up as
the first page, then all additional responders reports on the following pages
of the report.
Some of the responder reports may be up to 30 minutes earlier or later than
the IC report time, so the primary key numbers may not match others from the
same incident, not to mention the letters from the last names.
How can I write the query parameter in the [ERptNo] field to search for the
IC primary key [ERNo] (year, month, date, hour & minute) plus or minus 30
minutes to include all responder reports, and then a wildcard to bring up all
of the different last name letters? I'm just a beginner in writing code, so
if this is possible, a detailed explanation would be appreciated.
Thank you