Usually redis is used as caching service but it can also be used for publish and subscribe. Checkout this repo https://github.com/mail4hafij/redis_cache_dotnet_core if you are interested how to cache using redis.
There are two projects in this solution. Run the subscriber project first and then run the publisher. But first, setup a redis on docker as follows.
https://redis.io/docs/getting-started/install-stack/docker/
redis/redis-stack - contains both Redis Stack server and RedisInsight. This container is best for local development because you can use the embedded RedisInsight to visualize your data.
docker run -d --name redis-stack -p 6379:6379 -p 8001:8001 redis/redis-stack:latest
The docker run command above also exposes RedisInsight on port 8001. You can use RedisInsight by pointing your browser to localhost:8001.
Enjoy!