London day trip advice please

[SmallistChild]

Hi being a bit lazy here as hoping for advice. My elderly parents are visiting London for a day. I would like ideas to entertain them. They will be staying in Marylebone. Mother cannot walk far, but Father would be interested in the Tate modern, China Town and the paintings you used to be able to buy at Hyde Park, also Camden markets or is that just weekends? Thank you in advance for your help. Mummy will be happy to stay in hotel if I do the further places with my Father. Recommendations as to where to go and how to get there please. They both went to uni in London many years ago. They are visiting on a Tues 18 June if that helps re exhibitions and what is open. I live in the UK, but rarely go to London. I should more often really. Thank you

If you want to include everyone then maybe:
https://topviewtix.com/london/?gad_source=1&gclid=Cj0KCQjw3tCyBhDBARIsAEY0XNlx_Nd_wXWNFBKh49YXb61illGsXe19Sz1kqrqPpmWq4YGILRSjdWUaAuqcEALw_wcB

There are tourist paintings right by Green park station(jubilee line from Baker Street which should be easy walking from Marylebone but which is closest station?)

you can then take jubilee to Tate modern

china town is close to Piccadilly Circus or Leicester Square stations

Jubilee Line to Westminster and then get the river boat to Tate Modern as there's a pier outside. Mum could have a coffee in the cafe or in the cafe at the Globe if it gets a bit much.

Wow thank you everyone for your suggestions. Will sent this thread to M&d and see what they think. Really helpful thank you

I really wouldn’t bother with china town in London, it’s a bit crap, just loads of restaurants. I think you should book a nice place for afternoon tea so they can have a sit and a rest.

My Dad would probably but up for China, town, but agree afternoon tea, might suit Mummy more. I will see what she says thanks for all the Ideas.