I want to deploy ( Install ) latest Windows 10 Feature Pack ( Creator update ) to machines which are having older version of Windows 10. How can I do this to apply deploy job to specific machines having older versions?

SapphireIMS collects corresponding build number of Windows OS version as part of inventory operating system details. You may refer following articles to understand the respective build number of specific versions.

Using this respective build number, you will have to create base line rule. Please refer following link for configuring baseline rule. You may add multiple condition with inventory parameters using AND/OR rules -
http://www.sapphireims.com/help/compliance_baseline_rules.htm

Once baseline rule is created, you will have to follow below link to configure Windows 10 feature pack deploy job -
http://www.sapphireims.com/help/Windows_10_Feature_Pack_Deployment.htm

Please note that you will have to use the baseline profile configured as part of Choose Inclusion Host Profiles → Type Baseline Compliant Nodes so that job gets applied to machines which is of your interest.

There is another article on configuration and troubleshooting which you may refer - What are the steps to be carried out to configure and deploy Windows 10 Feature Creator Update and what are the troubleshooting steps?