Help on creating an invoice

Hi all my first post so i am trying to make it as detailed as possible
ok so I have 5 tables these are

tblCustomer
(PK)CustomerID
FirstName
LastName
Address
PostCode
ContactTelephone

tblEmployee
(PK)EmployeeID
Initals
FirstName
LastName
Address
PostCode
ContactTelephone
Email

tblVehicle
(PK)VehicleID
Make
Model
VehicleReg
EngineSize
NoDoors
Style
Transmission
Fuel
Colour
Milage
ServiceHistory
Notes
AskingPrice
PurchaseDate
SaleDate
PurchasePrice
SalePrice
Sold
SalesPerson (Linked to tblEmployee - Initials)

tblInvoice
(PK)InvoiceNumber
InvoiceDate
CustomerID (Linked to tblCutomer - (PK)CustomerID)
EmployeeID (Linked to tblEmployee - (PK)EmployeeID)

tblInvoiceDetails
(PK)DetailsUniqueKey
InvoiceNumber (Linked to tblInvoice - (PK)InvoiceNumber)
VehicleID (Linked to tblVehicle - (PK)VehicleID)

I want to people to go to the a form select the customer ID and Vehicle ID and the Employee Initials and then click on a button that will produce a invoice into Word which will show the Cutomer Name and Address then the Invoice Number (which I would like to be automatic in the table it is set as 'AutoNumber' anyway) then I would like it to show the Vehicle Make Model Vehicle Reg and then the Sale Date and Sale Price.

Any help would be appreciated

If this is too complicated to explain could you show me any manuals or help videos that could help

Much appreciated

Rob