I bought a new Samsung A54 last year with dual sim. Both sim slots work in all the countries I've visited, like Thailand, Indonesia, Vietnam and Australia.
the official Vietnam Government evisa website is this one. It costs $25 USD and takes around 3 to 5 working days to get. It's all done online. Here is the link:
personally I get the tourist visa rather than extending because I don't like attending Thai Immigration offices and because then I can extend that tourist visa afterwards if I really want too.
If you hit the yellow Krungsri ATM you can pull out 30k at a time. ATM fee will be 220 baht.. ..but, if your bank charges a foreign transfer fee then it isn't worth it and the Wise card is better. Good luck.
Most Thai people work very long hours and add in the travel to and from home means they are tired. So they can buy a somtum for 40 baht and a sticky rice for 10 baht why wouldn't they? It's already done with no ingredients to buy. As for washing clothes I'd guess 90% of them would do it themselves. The ones that are retired or don't work would most likely do everything for themselves too.