Do a Google search on this. You will find a bunch of articles on it, most of them unfavorable to Trump. But here's my take:

The famous Arlington military cemetery requires permission to arrive, permission for number in party, restricts photography 'not allowed for political purposes, but OK for personal,' etc., and many other such rules as it receives hundreds of visits annually and they must be managed to protect the facility.

The Afghanistan departure-related Gold Star families who came to memorialize the 3-yr anniversary of their family members' deaths had invited Trump and his photographer to come and mark the moment. Trump agreed to do so. All of them said they had reached out to Joe and Kamala many times over the past 3 years for acknowledgment and had received no response each time.

Prior to scheduling the visit, the families had to file the proper paperwork to arrive together, include Pres. Trump & have a professional photographer (Trump's) memorialize the moment. Arlington gave them pushback and eventually relented and allowed it. (Was the person who works there an anti-Trumper?)

When they all arrived, a person on duty refused to allow Trump's team and photographer through, claiming rules not followed. They had to employ Speaker of the House Mike Johnson (?) who finessed the situation and allowed the memorial to proceed.

When the Gold Star families posted images of the wreath ceremony, the Left got all riled up, saying it was a photo op for Trump and was 'political' and thus should not have been allowed.