Follow the below step for FSL package installation
Field Service Lightning should be enabled in salesforce org.
Click the appropriate installation link on the download page https://fsl.secure.force.com/install. You can install on a production org or a sandbox org.
Select Install for Admins Only. If you receive a request to approve third-party access, click Yes and Continue. This request allows Salesforce to collect the latitude and longitude values for service addresses so that the service scheduling optimizer can function.
If you get a message notifying you that the installation is taking longer than expected, click Done. Once the installation is complete, you will receive an email notification.
Refer this link
https://help.salesforce.com/articleView?id=fs_enable.htm&type=5
Follow the below step for FSL package installation
- Field Service Lightning should be enabled in salesforce org.
- Click the appropriate installation link on the download page https://fsl.secure.force.com/install. You can install on a production org or a sandbox org.
- Select Install for Admins Only.
- If you get a message notifying you that the installation is taking longer than expected, click Done.
ThanksIf you receive a request to approve third-party access, click Yes and Continue. This request allows Salesforce to collect the latitude and longitude values for service addresses so that the service scheduling optimizer can function.
Once the installation is complete, you will receive an email notification.