I’m a nut about brushing my kid’s teeth and have been since their first tooth popped through. I hadn’t though about flossing until my (now) 2 year old went for a check-up... you’ve got to floss between any teeth that touch, duh! My bad haha
Long story short - introducing floss into our am/pm routine was made so easy by the flavour of the floss. My son is obsessed with the smell and allows me to floss for him.
Mom trick... I let him pick a colour for him (to hold) and one for me easy time, then count to ten while I floss the bottom and the top.