Hello @TW_Tones.
Of course I’m happy!!! Instead of one solution I have two. 
Just yesterday I was trying to use the code that @tw-FRed gave me along with what I already had previously to create tiddlers from pre-defined templates, and in the end I got everything working correctly.
With the last modification proposed by @Thomas_Chuffart and again made by @tw-FRed it even fits me much better.
Please, when you have something that you think is ready to share with us I would be happy to try it and see how it works. 
Thank you very much to everyone who has helped me directly or indirectly with this problem, this is the best thing this community has.
Thanks again and have a good day.