When working with the Active Choice CheckBox parameter, you can select the default values by adding the ": selected" parameter
Pipeline:
properties([ parameters([ [$class: 'CascadeChoiceParameter', choiceType: 'PT_CHECKBOX', description: 'Select environment', filterLength: 1, filterable: false, name: 'Environment', script: [ $class: 'GroovyScript', script: [ classpath: [], sandbox: false, script: 'return[\'Development:selected\',\'Production:selected\']' ] ] ] ]) ])
When assembling with parameters, two environments at once, "Development" and "Production" will be selected by default