The public memorial for Charlie Kirk, the conservative activist and close ally of President Trump who was assassinated last week, will take place in Arizona on Sunday morning.

The service comes amid a public outpouring of grief, as well as aggressive moves from conservatives who have vowed to crack down on liberal groups and people who engage in what they see as hateful commentary. Among those conservatives are top officials in the Trump administration, many of whom plan to speak at Mr. Kirk’s memorial.

Here’s what you need to know about the event:

Where and when will it take place?

The program will be held at State Farm Stadium in Glendale, Ariz., a suburb of Phoenix, where Mr. Kirk’s conservative advocacy organization, Turning Point USA, is based. Mr. Kirk also lived in Scottsdale, another Phoenix suburb, with his family for several years.

Admission to the funeral, which is free, will be on a “first-come, first-served” basis, according to a webpage posted by Turning Point, which is hosting the event. The organization is inviting prospective attendees to register for tickets online in advance.

State Farm Stadium — home of the N.F.L.’s Arizona Cardinals — has a fixed capacity of at least 63,000 people, though that can be expanded to over 73,000 for larger events, according to the venue’s website. If attendance exceeds the stadium’s capacity, the neighboring Desert Diamond Arena, which can hold 19,000 people for concert events, will host overflow seating. According to Turning Point’s webpage, doors for the event will open at 8 a.m. local time, and the program will begin at 11 a.m.

Who will speak?

President Trump and several top administration officials are expected to speak, a testament to Mr. Kirk’s vast influence in conservative politics and deep connections to the Trump White House.

That includes Vice President JD Vance, who considered himself Mr. Kirk’s friend and whose political ascendancy Mr. Kirk championed.

Cabinet members who will speak include Marco Rubio, secretary of state; Pete Hegseth, secretary of defense; Tulsi Gabbard, director of national intelligence; Susie Wiles, White House chief of staff; and Stephen Miller, deputy chief of staff and the architect of Mr. Trump’s domestic policy agenda.

Mr. Kirk’s widow, Erika Kirk, who has taken over the leadership of Turning Point USA following Mr. Kirk’s assassination, will speak as well.

Tucker Carlson, the conservative media personality and former Fox News host, and Donald Trump Jr. will deliver remarks, too.

Scores of other elected officials and prominent conservatives will be attending.

The service will also feature several Christian music artists, including Chris Tomlin and Brandon Lake, according to the Turning Point webpage.

What do attendees need to know?

Turning Point has told attendees to expect tight security, which may extend wait times to get into the stadium.

The Department of Homeland Security designated the service as a top-level security event, similar to the Super Bowl or New York Marathon.

The organization said it will not admit anyone bringing a bag. It posted an additional list of banned items — including strollers, signs and “weapons of any kind” — on its webpage for the service.

Parking is free, according to the webpage, but Turning Point is advising attendees to arrive early.

The organization is also requesting those in attendance to dress in their “Sunday Best,” and wear red, white or blue.

How can others watch?

According to Turning Point, the event will be live-streamed on Mr. Kirk’s Rumble account. Some news outlets, including Fox News and ABC News Live, also plan to broadcast the event.

Jack Healy contributed reporting.