How do I reset the numbering in a set of steps in RH2019 New UI?

Thanks Peter, the second approach works. I had tried the first approach, bu there was no Bullets and Numbering option on the context menu.

Put the cursor at the start of the text by the second 1. Right click, select Bullets and Numbering and there's a field to restart the numbering. Set it to 4 in this case.

There is an easier way of you want the image indented with the text of the list. After the last character in item 3, press Shift Enter once or twice to get the space you want above the image. Then insert the image.

Use Shift Enter again if you want some space below as well. Then press Enter only and the list will restart at 4.