How

Just copy this

host: localhost                 # host name or address
port: 6379                      # you can specify either port
# socket: /run/redis.socket     # or unix socket path
# service: redis                # or service name
password: "pass"                # if not specified then no password used
database: 0                     # database number to connect to
max-connections: 5              # max connections in pool
max-idle-time: 30               # keep connection open for 30 seconds
timeout: 30                     # connection timeout

to your config file, then

import Data.Yaml
import Database.Redis.Config

main :: IO ()
main = do
    conn <- decodeFile "config/redis.yml" >>= \case
        Nothing -> fail "Could not parse redis.conf"
        Just conf -> connectRedis conf
    run conn

Thats all, you already working with Redis connection