Although you can create a rule with the merchendizer you can only use that to boost products.
To create this rule within Algolia, you can use the Algolia dashboard or send the rule to Algolia with code.
See this guide on creating a rule condition with a filter, expanded on here.
You should ensure that the rules you create don't conflict with the existing rules you may have created in Magento.
You also shouldn't edit any rules in the dashboard that may be overwritten by changes you make in Magento.
