Re: first Sailboat and first sail from Annapolis to Washington NC
3 days down the Chesapeake to Norfolk/Portsmouth.
2 days down to the Pamlico
3 or likely 4 days to Washington NC
These times expect 5 knots minimum.
Use an ap on your smartphone for current flows called "currents".
Search around for bridge opening schedules in Norfolk, there are strict limits and rush hour closures.
No allowance for surprises like engine trouble, bad weather, fouled crab traps.