Share video from iMovie ver 10.4 on MacBook Pro - change of aspect ratio
I am using iMovie version 10.4 on a MacBook Pro 2021, chip: Apple M1 Pro, mac OS 2 Sonoma 14.2.1, to convert six, .dv video files created in an old version of iMovie (aspect ratio 4:3). So far the conversions performed on my current Macbook Pro have produced MPEG 4 files in a 16:9 aspect ratio. Does my version of iMovie (10.4) enable creation of a file in 4:3 format for viewing on social media, or televisions. If it is possible, where would I find the instructions. Alternatively is there another way to combine the .dv files (4:3) and retain the existing format.
MacBook Pro 16″, macOS 14.2