You mean like this:

What was Trump actually doing on 9/11? An anniversary fact check. By Gillian Brockell September 11, 2019 at 1:03 p.m. MDT

At a 9/11 commemoration at the Pentagon on Wednesday, President Trump expanded on his lengthy history of recollections of Sept. 11, 2001, and its aftermath.

Before digging in, it is worth quoting at length.

I vividly remember when I first heard the news. I was sitting at home watching a major business television show early that morning. Jack Welch, the legendary head of General Electric, was about to be interviewed, when all of a sudden, they cut away.
At first, there were different reports: “It was a boiler fire.” But I knew that boilers aren’t at the top of a building. “It was a kitchen explosion in Windows on the World.” Nobody really knew what happened. There was great confusion.
I was looking out of a window from a building at Midtown Manhattan, directly at the World Trade Center, when I saw a second plane at a tremendous speed go into the second tower. It was then that I realized the world was going to change.
…
Soon after, I went down to Ground Zero with men who worked for me to try to help in any little way that we could.

Okay, let’s unpack this.

As the millions of Americans who witnessed the worst terrorist attack in U.S. history on live TV can attest, news shows did cut away from regularly scheduled segments to broadcast a live view of the World Trade Center towers after the first plane hit. Those same millions watched with horror as the second plane struck the second tower a few minutes later.

But Trump’s claim here is a little different. He said he “was looking out of a window from a building at Midtown Manhattan” that he had previously identified as his “home” when he watched the second plane hit with his own eyes, not on TV. AD

Trump’s penthouse at Trump Tower is on the 58th floor — high in the New York skyline — so it is possible that he had an unimpeded view of the World Trade Center all the way down on the southern end of Manhattan.

On 9/11, as the Pentagon burned, the White House couldn't find Donald Rumsfeld

There are reasons to be skeptical, though. While on the campaign trail in 2015, he told rallygoers:

“I have a window in my apartment that specifically was aimed at the World Trade Center because of the beauty of the whole Downtown Manhattan. And I watched as people jumped, and I watched the second plane come in.”

This an odd claim, considering that Trump Tower was four miles from the World Trade Center, and it would have been difficult to see people jumping from that distance. But for those millions who watched on TV, the sight of people jumping can never be forgotten.