Real project done as training session on Power Apps Dynamics 365 and SQL

I want to create a Power App to add purchase orders to a besoke Dataverse table. Products are pulled from an existing products table on SQL. Customer details are on a Dynamics 365 Sales model. User will select customer then add a number of products. Sected customer ID will be written to new bespoke table with sectected products. This is a real requorement but i have not done this before. I woul like to use this as a way of learning Power platform. I will need a few sessons to work though how this is done with myself and show me how it is done as a recorded Teams session. Please quote for an intial 4 hours for me to explain the project and you to start. Note must have very good spoken English ....