The best opening move for 4-1 in backgammon is 24/23 13/9. A builder and a small split. Watch it on the board, then read the idea behind it.
The idea behind the move
With 4-1 play 24/23 13/9: one back checker takes a small step, and a checker from the 13-point comes down to the 9-point, aimed at the 5-point.
What comes next
That gives you a builder and a little more freedom in the back. Your next aim is the 5- or 4-point.
How to read the move
A move like 24/18 means one checker goes from your 24-point to your 18-point. Points are counted from your side: 24 is the farthest, 1 is the deepest in your home board. “(2)” after a move means you play it with two checkers.