Yes they should be able to marry. Marriage laws don't generally care about Immigration status or misdemeanor crimes. However, the marriage may or may not grant citizenship rights, there's no guarantee of that.
'Illegal alien citizen' is an oxymoron.
No. A baby born in the USA is automatically a citizen, but the mother is still illegal.
Getting married to an American citizen.
it is illegal
No, his mother was a US citizen, he is a US citizen.
No. He or she can and will be deported when the authorities notice his or her legal status.
Is the Canadian citizen also an American citizen or holds citizenship. if so then yes if not then. Technically no. This is because neither party holds a current American citizenship. If the Illegal alien was to marry upon Canadian territory then apply for american citizenship or Visa. But other wise legally no. However they should check.
If they are an adult their status is still the same, they are an illegal alien.
Unfortunately, an illegal alien can not become an US citizen if they have been deported before. If they have a felony, they can't become a US citizen either.
Yes.
Yes.
I think it is a federal crime to offer services to an illegal alien, not sure if that bill passed or not...