Is it possible to trim some middle part of a video or screen recording on the iPhone or iPad to upload to YouTube?

I know how to trim start and trim end of a video or screen recording on the iPhone or iPad and upload to YouTube. But what if there are a few seconds in the video showing my user ID and I hope to blur it out or cut that few seconds out, is that possible inside of iPhone or iPad? One way is, I can trim the original into two videos. So for example, if the original video is 00:00 to 03:00, and I want to remove 02:00 to 02:06, then I can trim start / end to make video 1 as 00:00 to 2:00 and video 2 as 2:06 to 03:00 and then I have removed 02:00 to 02:06, but now I have two separate videos. Can I still somehow join them or upload to YouTube as 1 video?