Wish Fulfilling Mantra/Dilgo books

Hello,

I’m looking to get back into my Buddhist practice, and I was thinking of using the two books by Dilgo Khyentse Rinpoche:

Wish Fulfilling Mantra

Heart Treasure of the Enlightened Ones

I’m aiming my practice to be heart centered & devotional. Do you think someone could study and use these books only and build a successful practice?