In his Rule, St. Benedict speaks of the practices that monks will take up during Lent.

Illumination featuring St. Benedict at a book.
Designed by a monk of Fontgombault.
This rule, written almost one thousand five hundred years ago, describes choosing Lenten practices in a way that is very familiar to Catholics today. The monks are told to choose some extra prayers or penance, with the approval of the abbot, in order to sanctify the time as they prepare with joy for the great Feast of Easter.
But there is another practice described by Saint Benedict that is much less known and much less followed. The monk, in the mind of St. Benedict, is supposed to incorporate another aspect to his Lenten observance that will greatly enrich his prayers and penance: the Lenten Book….
The Lenten book can be considered as important as the practices of prayer and penance. But it is much less well known among Catholics. St. Benedict prescribes:
In Lent moreover let them each have a book from the library and read it all straight through: and these books are to be given out at the beginning of Lent. (Holy Rule, Chp. 48)
We should notice that not only does the Father of Western Monasticism lay down the rule of receiving a book, but he also gives two principles about how it is to be read. The book should be read as a whole and in order. It is not the occasion to read through random passages as if one’s whimsical curiosity is going to attract the movement of the Holy Spirit. Nor will it suffice to merely choose the best parts: it is to be read through completely and in order.
The book is also received by the monk and not chosen. It is a good practice to ask for advice about our spiritual reading because it is hard to know what to read when we have not read everything. This practice of taking a reading recommendation and following it through in order to the end can nourish our mind while also humbling our will and making us docile to the movement of the Spirit.
So ask someone for a recommendation, or choose from one of these below: