Some links/videos I think you will find useful
The Mister Teach- pre cursive letter videos are amazing. Take a look.
Epic Phonics- this video takes letter formation back to basics. Showing where to start and end each letter.
https://www.youtube.com/watch?v=TYYSBProJH4 (to music)
https://www.youtube.com/c/EpicPhonics/videos (Their channel page- gives access to each letter and its matching RWI rhyme)
Teach handwriting- looking at continuous cursive for beginners.