How to help my 5 year old keep developing?



For those with experience, what’s the best way to keep my 5 year old son engaged & improving?
That is great
At that age, it is more about keeping the game fun for them and letting them play at their own pace. Naturally, coaching could help them improve even more, but that isn't cheap and only helps if they WANT to work on their own chess improvement.
A good motivator might just be to find some people they can play often to give them some (but not too much) challenge and preferably around their own age. Children who get good at chess really young and stick with it usually (but not always) seem to have other chess friends to interact with. Not all of this is as a rival or opponent; some of this is just having others to interact with and "share" the same chess experiences with.
It is also very common for children to like chess, learn the rules (maybe play a little) and then lose interest in it for a few years. This isn't necessarily a bad thing either; especially if they have a good feeling regarding chess. Those people typically get drawn back into chess around teenage or young adult years and then they are into chess for good - I would know because I was one of those kids I learned the rules when I was young, but hardly ever played chess. It wasn't until around the time of starting college that I got back into chess, but now it's been about 5 years of chess since then
Just keep chess fun for them and if they feel good about the game, then even if they temporarily leave the game, it won't necessarily leave them
@1
Play games with him. Analyse with him. Buy him a book.
Bobby Fischer Teaches Chess - Fischer
Chess: 5334 Problems, Combinations and Games - Polgar

You might check out my chess.com blog....it is essentially a repository of many helpful and instructive resources including chess book recommendations.....I believe some of the articles may be of interest to you....
https://www.chess.com/blog/RussBell
In particular, I recommend to check out the following blog article...i.e., recommendations for specific resources for teaching chess to kids (and beginners of any age)...
Chess Courses - Instructional Resources...
https://www.chess.com/blog/RussBell/beginners-chess-course-instructional-resources
I suggest to begin with Volume 1 of Lev Alburt's "Comprehensive Chess Course" - it is an introductory instructional resource especially suitable for teaching chess to small children.
Note that both volumes of Lev Alburt's course can be viewed and downloaded for free from PDFdrive*dot*com...
Scribd and PDFdrive For Online Chess Book Reading, Downloading...
https://www.chess.com/blog/RussBell/scribd-com-for-online-chess-book-reading
PDFdrive and Scribd are safe. I've used them both extensively to download PDF copies of dozens of chess books over the years..

Most imortant thing is to constantly motivate him to play as many games as possiblle. Also working on tactics if preferable and teaching most imortant chess principles and explaining them to your kid in his games... Let him enyoy and play as much as he can. Be careful with first kids tournaments. Best regards Ivan
For those with experience, what’s the best way to keep my 5 year old son engaged & improving?