How to create mulitiple zoom meeting for my boss making him the co-host

You can create a recurring meeting with a generated ID. In edit at the bottom under "advanced" you can assign and alternate. If you prefer you can schedule 4 separate meetings.

Welcome to the Zoom Community, @cathyK.

You can’t make someone a cohost in advance. This has to be done once the meeting has started, and only when the person to be designated Cohost is in the session. 

Assuming you are both on the same company account and both are Licensed (paid) accounts, the easiest way is probably to set him as Alternate Host for each of the four meetings.

See this Zoom Support article for information on how to designate an Alternate Host, and the limitations:

https://support.zoom.us/hc/en-us/articles/208220166-Designating-an-alternative-host