This might get you started but you might have to google the syntax.

(New Module)
Global ac as Object

Sub openAccess()
Set ac = CreateObject("Access.Application")
ac.visible = true 'Ignore this if you want it to run in the background

ac.OpenCurrentDatabase "Path to your database"

ac.OpenReport "Your report"

'or try this
ac.DoCmd.OutputTo acOutputReport, "yourReportName", acFormatPDF, "OutputPath" & ".pdf"

ac.DoCmd 
End sub
When you use the ac object, you have full control over the access application as you would if you had it open (I think). I've only used it once, and it was a while ago.
Best of luck!