Please format your post correctly in future, see: https://community.home-assistant.io/t/how-to-help-us-help-you-or-how-to-ask-a-good-question/114371#oneone-format-it-properly-16
action: input_number.set_value
metadata: {}
data:
value_template: "{{ range(1, 3) | random }}"
target:
entity_id: input_number.christmaslight
value_template should just be value.
https://www.home-assistant.io/integrations/input_number/#actions
There are examples on that page too.