I don't know for certain that Paul prayed the Lord's prayer, but he did say many times to be in constant prayer:
Prayer is not a mantra or a rote set of sentences that you say 1000 times that you have done so many times that your mind is not even thinking about it.
As in that case you are just getting to the last words so that you can stop, and go get a cookie and some cake.
Real Prayer is conversation with God from your heart.
Prayer is you and The Father having a 2-way interaction...
Prayer is you giving God sincere thanks for the Cross of Christ, for the blood of Jesus, that is the only reason God is your Father, and in this thankful state of mind and heart you then tell God all about it.. All about what is going on with you.......all about your needs..... all about your hopes and dreams.
Prayer should follow a bit of worship and praise then requests.
Reader, do you know why Jesus has ears?
So that God can hear you when you pray.
He does.
You dont know how to pray? Feel not so comfortable with it.?
Try it like this., early am...... and on your knees is best....if possible.
"Good morning Father, Lord Jesus, and Holy Spirit, you are welcome here."....
It was Mother Teresa who taught me to start my daily prayer with "Good morning, you are welcome here"" = to the Father, the Son, and the Holy Spirit.
Try it for yourself, Saint.
Here is how i pray.....see if you can use it as an idea for yourself.
"""Father God you are so good, you are so Holy..... you name is Holy. You are all rightness, and goodness and love and beauty.
You are the Father of creation, the Father of Grace, the Father of Love the Father of the Bread come down from heaven, and Father God i thank you for Jesus.....for the bless'd Savior, the King of Glory, the Living Hope.
Thank you sweet Bread of Heaven. Thank you for your Blood and your Cross. There is power in your blood, there is healing in your blood.
Thank you Lord for coming into this evil world to rescue us, to save us, to give us your Salvation.. Jesus, yours is the sweetest name there ever was and Yeshua yours is the sweetest name that ever will be. You are beautiful, you are King, and you are life, and every knee shall bow and every tongue shall confess that you are Lord, you are Lord, you are Lord of all.
Sweet Bread of Heaven, your name is above every name. And Lord you are God's Grace, you are God's forgiveness, You are God's Redemption and Redeemer and Eternal life. You are the Love of God, the Grace of God and the Gift of God. You alone are my salvation, you alone are my eternal life, and Lord i thank you i thank you i thank you for being my King, my Savior, my hope and my peace..""""
Try it kinda like that Saint.
God bless you.