otf.msn.com
otf.msn.com
accounts.google.com
Email=adresemail@gmail.com
www.x-kom.pl
login=exampleelog
allegro.pl
ssl.allegro.pl
www.bing.com
www.bing.com
www.bing.com
www.bing.com
store.steampowered.com
username=steamaccountereed
login.live.com
login=mailhotmail@hotmail.com
www.bing.com

grep -oP '(K[^)]*|(user=|username=|Email=|login=)[^&]*' file.txt

grep -P '^(?=.*@.*)' file.txt

if "its username or mail"
  if [email condtion]
   then write emails to emails tab
else
write to users tab
else
 write it to 'site' table

Choose mail to send a massage:
mailhotmail@hotmail.com
adresmail@gmail.com

Choose site :
steampowered.com - username=steamaccountereed
x-kom.pl - login=exampleelog

$ cat tst.awk
{ $0 = tolower($0) }
sub(/^(login|username)=/,"") { vals["LOGINS"][$0] }
{ sub(/^email=/,"") }
/@/  { vals["EMAILS"][$0] }
/./ { sub(/[^@]+@/,""); vals["SITES"][$0] }
END {
    for (type in vals) {
        print type ":"
        for (val in vals[type]) {
            print "t" val
        }
    }
}

$ awk -f tst.awk file
SITES:
        www.bing.com
        allegro.pl
        gmail.com
        accounts.google.com
        hotmail.com
        otf.msn.com
        www.x-kom.pl
        login.live.com
        store.steampowered.com
        ssl.allegro.pl
LOGINS:
        mailhotmail@hotmail.com
        steamaccountereed
        exampleelog
EMAILS:
        adresemail@gmail.com
        mailhotmail@hotmail.com