Book Trailer—help needed

Can anyone help OR tell me how to make a one-minute trailer for my Journeys Through Life series with on Windows or an iPhone? I have 9 photos and text to use. It’s hard because I’m trying to cover both books in the series, which have different subjects, but I think I have it figured out.

I want to do it myself, but I don’t know where to begin, and I want to make sure there’s enough time before the slides move on to the next one. I have the number of seconds I’d like each picture to show—can these times vary between photos?

If I pay someone on Fiverr, they may not care about the timing. What is the longest I should make the video? Also, should I add the text directly to my photos, OR is that done in whatever program I use? Thanks!