First, visit this site and search for the emoji you want.
If you found the emoji you're looking for, select it and scrolling down by selecting that emoji you'll find Unicode(example: 😀 U+1F600) below the "Codepoints". Copy it to paste it in your code.
Then, remove "+" from it,
U+1F600 -> U1F600.
Put, backslash before "U" and three zeros after "U".
Now, print it..
std::cout<<"\U0001F600"; \\ 😀
Still, facing any errors? Feel free to ping me. :D
Hope this will be helpful. :)
I copy pasted the emoji icon for example here.
On Windows 10 try win key and + combination.
When writing code your mobile keyboard may not show emoji option. I don't use Gboard keyboard may be that has an option still enabled.