You can repeat this process several times to create multiple ad units - in that case be sure to assign all ad units to other entities in other steps of this guide.
In Google Ad Manager’s side menu, under Inventory, navigate to the ad units page
Click ‘New ad unit’
Name the ad unit according to your naming conventions, but include ‘BrowsiVideo’ in the name. If your naming includes forward slashes - / ‘BrowsiVideo’ should come after the last slash
Code should be identical to the ad unit’s name
Description can be left empty
Under sizes, set size mode to fixed
For the video master size, select 1x1v from the list of options
Everything else in this section can be left empty
All other inputs in this page can be ignored - scroll down and save