Good program but a big hiccup from me. We barely got started and I discovered I had to download and set up Elasticsearch. There is also no data to work with, but the tutorial assumes seven todos in the Elasticsearch database. I suggest you add an Elasticsearch basic tutorial that includes using Kibana to enter the raw todos and make it a recommended prerequisite. Either that or add enough on Elasticsearch to get the student running and then put the PUT API first rather than last.
Try this out and let me know if it helps: I updated the repo to include a docker container with Elasticsearch and a utility to import the sample data into Elasticsearch. Detail on usage can be found here: https://github.com/rekibnikufesin/nodejs-api-swagger/tree/master#running-elasticsearch-and-sample-data
You'll need docker installed, but everything else should be included.