kokku - welcome to the forum.
When you make a call using Auto Attendant Option 2, the Auto Attendant will use its Primary Line to try to place the call unless you prefix the call with a ** code. The default for an OBi110 is:
Voice Service > Auto Attendant > PrimaryLine: PSTN Line
Quotea) gave the number 011912212345678 ( for calling india)
b) *008011912212345678 - to use the PSTN line
These did not work because the Auto Attendant is try to place the calls using the PSTN line, which is already busy as you are calling in on it. If GV is on sp1 then this should work **1011912212345678.
If you always want to call in on your PSTN line and use GV for calling out using the Auto Attendant, then you may wish to change its Primary Line as follows:
Voice Service > Auto Attendant > PrimaryLine: SP1 Service
Then you will not need to use the **1 code to select GV on sp1.