Redash dashboard prompt or filter

I’m using a Redash instance in GCP. Data is loaded into couple of BQ tables. I created a query like below:
select s.segment Segment, sum(e.sales_amt) Sales
from sample.lookup_segment s, sample.redash_example e
where s.customer = e.customer
group by s.segment

Now I want to include a dashboard prompts or filters for Segment and Customer fields. Noticed a checkbox to activate dashboard filter but not sure how I accomplish it for the above query. Can someone help please?

Either filters or parameters can work here. Notice that with filters the entire table is pulled into memory with special column aliases which may not perform as well. Parameters are passed directly to the database so they usually appear in you WHERE clause.

With Filters

SELECT
    s.segment "Segment::filter",
    s.customer "Customer::filter",
    SUM(e.sales_amt) Sales
FROM
    sample.lookup_segment s,
    sample.redash_example e
GROUP BY 1 , 2

With Parameters

SELECT
    s.segment Segment,
    SUM(e.sales_amt) Sales
FROM
    sample.lookup_segment s,
    sample.redash_example e
WHERE
    s.customer = '{{ customer_param }}'
GROUP BY 1