spam or no spam

recently i have been getting a lot of weird emails
i use yahoo mail and like all or most emailing sites yahoo identifies between spam and email and places them in different locations
today i checked my email account and received an email from person i dont know
i am expecting my group project members to email me things so i opened it just in case its one of group members

the email is not from my group members but from a widow
in the message she wrote that she wanted to share her late husband's assets to God loving people
so that they can use the money to do good like build charities and such
she wrote that if me or anyone who receives the message is God loving and willing to help then contact her by email

another one i received was from a realitor
the message was addressed to someone else so i deleted

and another weird email i received was from a lawyer
this was again addressed to the wrong person but it wasnt addressed to the same person as the letter from the realitor

i received the 3 emails in period of 2 weeks
so i am wondering if you can have really similar email address that is like 1 letter or number difference if this is possible it would explain why i am getting emails addressed to other people