How to encourage my cockatiel to talk?

Hey guys! I wanna encourage my shy cockatiel to talk in front of me.. like it does talk but whenever no one’s around and talks very much and very clearly.. the thing is I wanna make it comfortable with me so it can talk with me and I can encourage it to learn more things..

Also nowadays i have started to try to encourage it to talk with me by talking with it but it just makes a sound as if it is about to talk but then goes silent..

Is there anything i can do? Does anyone else have faced this too? Do tell me and help me thanks! ☺️