people of Bangladesh don't say goodbye as it is in English, these are same of the word which might help you.
Abar deka hoby (see you again)
Ekon Ashy (I will leave now)
bhalo teko (be safe)
Salamualikum. (peace be upon you, If you are addressing to muslim)
Adab (respect If you are addressing to hindu or buddist)
I hope this will be helpfull to you.
zabid
People in Canada speak English, so I imagine they would say 'bye'
"aabar dekha hobey"= we will meet again dunobad= goodbye (exetremly formal)
selika
masalama
uhi
adios
In Puerto Rico, people commonly say "¡Hola!" for hello and "Adiós" for goodbye. Additionally, a more informal way to say goodbye is "Chao."
People say goodbye as life is very uncertain, the two may not see each other next day as one could be dead.
say hello
what's goodbye in cebuano
see you later alligator
"Hello" is aloha, which can be used to greet people or say goodbye. Another way to say goodbye is a hui hou, which means "until we meet again."