Tools in Microsoft Advertising for creating, editing, and optimizing ad campaigns
Hi Sandy,
Content is only available in US, so that may be why you are not seeing this option. If you do have a US based account, the way to bulk change is select all campaigns on you campaign screen - then go to the Ad Groups tab, check all ad groups, go up to edit and select other changes.
In the US it looks something like this:
If you do not see this - Your account is probably optimized for UK settings only