You first need to log in with your admin login credentials in your worksuite app.

Login as super admin if you are using worksuite-saas

Worksuite: After logging in as admin, Go to Settings -> Module Settings -> Custom Modules. And now click on the Install-Module button.

Worksuite-SAAS: If you are using worksuite-saas then login as superadmin and go to Settings->custom modules

Download the latest files from the codecanyon of the Asset/Payroll/Subdomain/RestAPI module and Extract the zip file.
You will have to upload the ModuleName.zip (Example:- Asset.zip) file on the install module page.

After the upload, the file refreshes the page.
You will see the recently uploaded zip file. Click the Install button in front of it.
The module will be installed and you will be redirected to the login page.

You need to verify your module purchase for the seamless experience.

Step 5: New super-admin Login URL (only for Subdomain worksuite saas module)

Then new login URL for once you have installed the subdomain worksuite saas module will be changed from /login to /super-admin-login