Assigning staff to roles has several benefits including helping to ensure business continuity and improve communication, and is something we would recommend you do from the outset.
To add users to roles:
Click on Administration > Users Management and you'll see your User Management grid dashboard:
Identify the user to whom you wish to assign roles and, in the Action column, click on the Assign Roles button. The Assign Role to User dialog will display:
Note: You will likely add your assistant(s) to the Company Admin role.
Select the required roles and then click on the Save & Close button to assign the user to their new roles.
Next Steps
That's your company onboarding complete. Next steps are to get your assistant to invite your remaining employees and contractors, and to then begin creating your project documentation and projects.
Refer to Projects, SWMS, etc., for help with doing that.