Thanks, please tell me whether Deut 6:5; Mark 12:29 is unitarian or trinitarian?
They are Trinitarian.
Deuteronomy 6:4-5
(4) Hear, O Israel! The LORD is our God, the LORD is one!
(5) You shall love the LORD your God with all your heart and with all your soul and with all your might. (NASB)
Mark 12:29-30
(29) Jesus answered, “The foremost is, ‘HEAR, O ISRAEL! THE LORD OUR GOD IS ONE LORD;
(30) AND YOU SHALL LOVE THE LORD YOUR GOD WITH ALL YOUR HEART, AND WITH ALL YOUR SOUL, AND WITH ALL YOUR MIND, AND WITH ALL YOUR STRENGTH.’ (NASB)
The only one God of Deuteronomy 6:4 and Mark 12:29 is to be prayed unto (cf. Deuteronomy 6:5 and Mark 12:30), and since the Lord Jesus is properly prayed unto this necessitates that the one God of Deuteronomy 6:4 and Mark 12:29 encompasses the Lord Jesus.
1. Richard N. Longenecker: There is no commandment in the Jewish Scriptures that says simply "Thou shalt pray!" Rather, what one finds is a verse like Deut 11:13, which calls on Israel "to love the Lord your God and to serve Him with all your heart and with all your soul." The rabbis of the Talmud asked about this verse: "What kind of service is it that takes place in the heart"? And they answered their own question: "It is prayer!" (b. Ta' anith 2a) (Studies in Paul, Exegetical and Theological, page 33).
2. The Jewish Encyclopedia (1901): The word "tefillah" is defined as "thought" and "hope" (comp. Genesis 48:11), as representing the means of reasoning and discriminating (Comp. Exodus 9:4) between good and evil. A tefillah consists of two parts: (1) Benedictions, or praises of God's greatness and goodness, and expressions of gratitude for benefits received (2) petitions, of either a public or private character.
A tefillah is called a "service of the heart." "Ye shall serve the Lord your God" (Exodus 23:25) is understood as "Ye sall worship God in prayer." The Patriarchs were the first authors of prayers, and are credited with instituting those for the morning, afternoon, and evening (see Abudarham, "Ḥ ibbur Perush ha-Berakot weha-Tefillot," p. 8a, Venice, 1566). Moses was the author of the phrase, "a great God, a mighty, and a terrible" (Deuteronomy 10:17), which was incorporated into the opening of the ' Amidah (Yer. Ber. 7:3 Yoma 69b). David and Daniel prayed thrice daily (Psalm 55:17 Daniel 6:10). (Prayer, see "In Rabbinical Literature", the underlined is mine).
https://www.studylight.org/encyclopedias/tje/p/prayer.html