You should study portals and relationships. Check the help file or examples in Filemaker's free files.
One idea is to establish a relationship between employees and equipment based on the employee id. Now you can create a portal on a form in both files showing the related records in the other file. After you get this working you can move to the next step.
ID Emloyee ( a number field set to auto-enter)
ID Equipment ( a number field set to auto-enter)
ID employee ... the field used to establish the links.