You can opt into a sponsored Visa

The person from Guatemala will need to apply to immigrate into the United States of America.

It would likely be easier to marry your boyfriend in Guatemala and then file the I-130 petition for him to eventually be admitted to US and apply for her

For Him** sorry

Yeah I used to work in immigration and I agree, it's only easier to marry then move otherwise it's a very long long longgg process

If only I knew that, I went the long way out and ended up paying thousands in attorney fees lol........Now I'm all sorted though