What tools do I need if possible to create an interactive video using my Timeline Guides and Markers?
Do you mean for YouTube chapters? If so see here: Rendering — Kdenlive Manual 23.08 documentation
Maybe, but for now family and friends…, I will read the link provided, thanks!..
What is that exactly?
A video with chapters so you can jump to a any part or to another scene.
See also: Timeline->Guides->Export Guides
If you don’t want to split the original render into multiple parts.
But then you might need external tooling to add that exported file to the video in a way that your preferred container format and player both support.
That sort of thing is a bit of a not-terribly-well-standardised clusterfk, though it would be nice to be able to select options to do it during a normal render.