US Immigration from Sweden

My parents appointment at US embassy in Sweden is coming up and the vaccine is the only thing left and it has turned out to be the MOST difficult!
I can't emphasize how many countless hours I spent on the phone and driving around to clinics & still not having any idea what to do.

FYI: My parents are both above 65 years old

On this link: https://www.cdc.gov/immigrantrefugeehealth/panel-physicians/vaccinations.html

it says require Varicella. But I don't know what kind. I've been told there's AT LEAST 3 different varicella types:

Varivax, Shingrix eller Zostavax

I know this might be a bit medical but..if anyone knows, please do let me know.

also, since Varicella is chickenpox (and my parents have had vaccine for it many years ago BUT they do not have the proof anymore), do you guys think there's a chance their visa will be denied if they don't provide evidence of anti-bodies or vaccine proof ?
I been told this should not be given to immune compromised people which they both are
Thanks in advance

1st of all, I want to thank everyone who helped me out during this process. I seriously would have never been able to do it without this forum.

I thought after the i-864 forms etc, the difficult part was over. HOLY (remove), it definitely is not.

I got e-mails about them having an interview at embassy May 16th just days ago.
Please, you do not need to know the answers to ALL questions in order to respond. Any help is appreciated!

Q 1:

After this interview, do they get a greencard right away? Or do they get a VISA first ?

Q 2:
If they get a VISA and NOT a greencard to start with, how long does it usually take to get a greencard after their Visa?

Q 3:
My parents usually go to doctor 3 times a week for checkup. They will have $0 US income. They do have some small savings but I was wondering about health insurance. They are both over 65.
I know Medicare require u to have worked for at least x years to qualify. Are there any good zero cost health insurance in US (california, Los Angeles) that anyone knows of ?
Medical MIGHT work, just wanted to see if there's any other recommendations?

THANK YOU !!!!!!

I looked at the timeline on this website, and I don't understand ANY of it, in ANY SHAPE or form...
Sorry to bug you guys...if anyone has a few seconds to help out I would appreciate it.
I'm a US citizen submitted my i864 for both my parents who live in sweden just a month ago.
To my surprise, they already got the appointment at US embassy in stockholm in 1 month from now for a VISA application.
I'm just wondering, does anyone have ANY guesses on how long it takes from the interview day for them to actually be able to come to US?

Would be nice with just an estimate, that's all. Thank you

I'm a US citizen trying to do a petition for my sister that lives in Sweden and I'm currently working on the i-130 ONLINE application.
I just have some questions and would appreciate some help.

Q 1:

"At which U.S. Embassy or Consulate location will the beneficiary apply for an immigrant visa?"
Since my sister doesn't live in USA, I should put her hometown in that area correct?

Q 2:

In the section of "Evidence" -> "Evidence to support your petition", there's 3 sections on this page:

A) Proof of U.S. Citizenship
B) Evidence of the end of your prior marriage(s) (Upload documents showing that your prior marriage(s) were legally terminated.)
C) Proof of sibling relationship

On B, is it asking for my divorce papers? Or my sisters?

Q 3:

I don't see anywhere on the application where I need to provide passport copy of my sister. Am I not supposed to provide this with the i-130 form?

By the way, you don't need to know the answers to all 3 questions to respond.
Thanks a bunch!!

Just curious if moving to another state will cause the service center assignment to change as well? If so, would USCIS notify us that the service center assignment had changed? My wife's case was assigned to YSC, which appears to be one of the slowest when it comes to processing cases. We do intend to file her N-400 petition online next month (have to be in current state 3 months in order to file), but it would be nice to see some movement on her I-751 petition soon.