Old World is currently on sale, 10% off in the Epic Games Store, 29.69€ instead of 32.99€ (sale is for 2 days).
If you take the chance to get it now, and want to dig deeper, then our user alcaras has made a new video about training in Old World. Have a look at it if you want to know how to better manage your troops, and leave any comments about it here https://forums.civfanatics.com/threads/any-youtube-videos.675609/#post-16252711.