@Tal *********
If you, the collective you, are getting married (in other words, a person who is getting married), anyone who is getting married can use any witness.
>Does anyone know if I can be a witness for the marriage
Yes, anyone can be a witness.
In American English, the word "you" can be a plural and not singular.
"In modern-day English, there is only one form of you for formal, informal, singular and plural. "
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