how to type vowel forms "ঊঁ" & "ঊ" while typing in Bengali using Lipikaar?
Lipikaar is an SMS-style typing method. For the first character type the closest sounding English character: in your case first type ‘a’ to get া, similarly first type ‘u’ to get ু.
If you type ‘a’ again, you will get অ.
If you type ‘u’ again, you will get ূ.
The sequence for ‘a’ is: া অ আ ঊঁ
The sequence for ‘u’ is: ু ূ উ ঊ
Thus type ‘a’ and ‘u’ four times to get ঊঁ & ঊ respectively.