There are many bible verses telling us to encourage one another. Below is a sampling drawn from the new testament from NASB bible.
So then we pursue the things which make for peace and the building up of one another. [Romans 14:19]
Let the word of Christ richly dwell within you, with all wisdom teaching and admonishing one another with psalms and hymns and spiritual songs, singing with thankfulness in your hearts to God. [Colossians 3:16]
Therefore encourage one another and build up one another, just as you also are doing. [1 Thessalonians 5:11]
But encourage one another day after day, as long as it is still called “Today,” so that none of you will be hardened by the deceitfulness of sin. [Hebrews 3:13]
and let us consider how to stimulate one another to love and good deeds, not forsaking our own assembling together, as is the habit of some, but encouraging one another; and all the more as you see the day drawing near. [Hebrews 10:24-25]