Ok, see this video: https://www.youtube.com/watch?v=hq3yfQnllfQ
0.:16, you will hear "A for apple"
/eɪ fɔː ˈræp.l̩/ --> clearly the speaker linked
0.:18, you will hear "A for ant"
/eɪ fɔːr ænt/ --> clearly the speaker did not link
0.:18, you will hear "E for egg"
/iː fɔːr eɡ/ & "E for elephant"
/ˈel.ɪ.fənt/--> clearly the speaker did not link
SO, why sometimes we do link the last consonant of before word & the first vowel of after word & sometimes we don't?
Or is that because the English ability of the Kid in the video (even though she is a native) has some limits & that is why she didn't know how to link?