Very common beginner question.
When a selection is pasted initially it is a 'floating' selection layer. As you found easily movable while still in that 'mode'. There are then options to either merge down to the layer below 'Anchor', fixed for ever-more or promote to a new layer.
To move that new layer, use the move tool. For an image with multiple layers, the move tool finds the first layer under the cursor with a solid pixel and moves that layer. Very often the background layer. Two options. Make sure the cursor is on a solid pixel or Make sure the correct layer is active and use the 'Move active layer` option.
Also this is a common problem with text layers where there is a lot of transparency between the characters
When a selection is pasted initially it is a 'floating' selection layer. As you found easily movable while still in that 'mode'. There are then options to either merge down to the layer below 'Anchor', fixed for ever-more or promote to a new layer.
To move that new layer, use the move tool. For an image with multiple layers, the move tool finds the first layer under the cursor with a solid pixel and moves that layer. Very often the background layer. Two options. Make sure the cursor is on a solid pixel or Make sure the correct layer is active and use the 'Move active layer` option.
Also this is a common problem with text layers where there is a lot of transparency between the characters