Woocommmerce custom email notification

I have a question about woocommerce code I hope you could help because I found this item on your site so I give it a try:

https://premium.wpmudev.org/forums/topic/woocommerce-need-on-hold-email-notidfication-when-status-changes/

We are trying to build in something when an order is “processing” for lets say 2 days it must automatic send an email to the customers that we think on them and the order is almost on their way, so I found also this, but I can’t figure out can you maybe help?

https://stackoverflow.com/questions/55809783/send-a-custom-reminder-email-for-woocommerce-on-hold-orders-after-two-days