You may find the following links helpful.
How to potty train – NHS (www.nhs.uk)
Top 10 potty training tips | ERIC
https://www.eric.org.uk/Handlers/Download.ashx?IDMF=202c5144-c663-48e9-9bf2-4347699f3886
PT-Toilet-training-FINAL-VERSION-29.7.20.pdf (ihv.org.uk)
Potty training problems