Hi, 

the main benefits are better seating with 2+1 seating instead of 2+2. 

Drinks/Snacks/Meals are normaly not included.

To use first class on TGV services you need a first class Eurail pass or you buy a normal ticket. 

If you book via SNCF (online not possible) or via travel.b-europe you can upgrade most of the time for trips in france for not so much money if you have a second class Eurail Pass.

For your leg Lille-Paris with Eurostar you have to plan with another train, because you can't use Eurostar. Only possible for International rides.

For TGV Lyria you need a first class pass.

Eurostar 9141 is a train Brussels - Lille - London.

7035 - train: you travel in 1st class / station: none

9141 - doesn’t run from Lille to Paris and can’t be booked on this relation even if it would run there 

9210 - train: you travel in 1st class / station: none

If you did want to know what you’d get when travelling by 9141 from Lille to London, the answer is:

9141 - train: meal choice of two cold options, dessert, drink choice of wine, beer, soft drink / station: none

Thanks. I meant ES9141 as I booked 1st class from Lille to London. 
 

Also with 1st class tickets from Zurich to Paris, aren’t there any lounge access in Zurich station?

There’s no longer any lounge at Swiss stations. (If you were going in the other direction, Paris-Zurich, you might get access to the lounge in Paris. Regular first class ticket holders on TGV-Lyria do.)

Good info on first class lounge access here, from Seat61.

https://www.seat61.com/european-train-travel.htm#first-class-lounges

On the Eurostar you’ll get a light meal. It’s pleasant enough, well presented and comes with drinks, coffee etc. I think of it as like a small three course meal, but with the main course removed.

No inclusive food on the TGVs. No lounge access for any of the trains you’re taking. All will have roomier seating, and if you’re travelling solo you can get a solo seat.

Thank you very much. Very informative