Go to the Open Refine site to download the program and learn about features https://openrefine.org/
The Library Carpentry site has a good walk through for using Open Refine https://librarycarpentry.org/lc-open-refine/index.html
The Data Carpentry site also has Open Refine lessons, such as this one for Ecology https://datacarpentry.org/OpenRefine-ecology-lesson/
Datasets for practice
Library Carpentry https://librarycarpentry.org/lc-open-refine/data/doaj-article-sample.csv
Data Carpentry - Ecology
https://datacarpentry.org/OpenRefine-ecology-lesson/data/Portal_rodents_19772002_simplified.csv
Python notebook example from class https://colab.research.google.com/drive/1en1aWvzpLkyiUf5tNlNOlBkXdGkxG6ND?usp=sharing