The people of Israel were always cared for by the Lord, wherever this people stepped on was with the support of God who was with them.
In this case, the Bible says that Moses was already 120 years old and that is why he designates Joshua to follow God’s mission and purpose.
In chapter 31 of the book of Deuteronomy it says that Moses spoke these words to all Israel.
Let us remember that the Lord tells Moses that he could not pass from Jordan, but that Joshua, whom God had prepared with Moses, would be the person who would lead the people to the promised land. All nations that were against God and the people would be handed over to Joshua.
Be strong and of a good courage, fear not, nor be afraid of them: for the Lord thy God, he it is that doth go with thee; he will not fail thee, nor forsake thee.
This is the promise that God makes to Joshua since he was the one who was going to lead the people of Israel, who together with the people would fight in the battles to be able to take possession of those lands.
God tells Joshua to cheer up, strive and not be afraid, for God Himself was with him.
God is the One who goes with us, let us not be afraid of anything, He does not forsake us, He does not let us fight alone, God will always come to our forehead, and this is what happened with Joshua, because he trusted the Lord.