Question: I am new in Alexa skill kit development   

I have already read Tutorials on Alexa Skill Kit   

I have to implement Alexa Skill , In which I need to manually send command and want Alexa to speak it.

i.e When user login in system I can fire API as Alexa request and I want Alexa device to Speak that for example "Welcome Have a great day"

Is it Possible ? Or Any other alternatives. ?

Answer: 
Notifications for Alexa skill are in still in beta. You can apply for the access to it by filling up this form here : <https://alexa.au1.qualtrics.com/jfe/form/SV_72lplGGegxNZ9Ln>
If **Push Notifications** is what you're looking for, then the answer is ***YES***.

Since in the comments you said, *"You are not asking for HOW TO DO IT"*, so I'll just let this link here for your reference. <https://developer.amazon.com/docs/alexa-voice-service/notifications-overview.html>