TFL route help please

[Crunchiethatfridayfeeling]

Not sure if my title says what I mean correctly.
Next Monday I'd like to take my children to the national Maritime museum London and would like some help with the route please.
I'd like to go on the uber / River transport boat at least one way.
We aren't in London but will train to Tottenham Hale and then tube or we can go into Stratford or Liverpool st and then tube/train.

My route plan gives me the simplest route so doesn't have the boat option, does anyone know where I'd be best going to to get the boat to the museum.
I'm happy to take the easiest route back but would like to use the boat at least on the way there.
Thank you

I think what I'd do is get the Victoria Line to Victoria, then the Circle / District to Westminster and get on the boat there. Or maybe stay on the Circle / District for another couple of stops and get on the boat at Embankment or Blackfriars.

For the return run from Greenwich, it might be fun if you walk under the Greenwich foot tunnel and pick up the Docklands Light Railway (no driver, the children might get to sit in the front if they are lucky!) at Island Gardens, get off at Bank and take the Northern Line to Kings Cross. The DLR is elevated track almost all the way so plenty to see. From there you can pick up the Victoria Line back to Tottenham Hail.

Definitely agree with taking the Victoria line from Tottenham. With the TFL app you can tweak your options a bit so they might show a better route in future. Also, Citymapper App is great for getting around. It gives you options and timings of transport and might help your journey back if you end up somewhere you aren’t sure about or there’s a problem on a line.

Download Citymapper app it’s the best for public transport in big cities

Thank you so much for your replies, they're all very helpful.
Will download citymapper.
I love the DLR on the way back idea too.

Fingers crossed for a dry day 🤞