How to get input_select entity id and save it in a variable in a blueprint

Configuration Blueprints
2

the target selector will allow you to choose multiple entities. You can also set the entity type to only allow users to select lights.

input:
    input_light:
      name: Target lights
        selector:
          target:
            entity:
              domain: light

variables:
  input_light_val: !input input_light