Is it possible to give names to the polylines in ArcGIS 10.3?
what is the name of the tool?
There's no specific tool required. You need to have information in the attribute table of your polyline layer. This information will then be displayed should you configure the labeling options of the layer.
Right click on your layer and select open attribute table. If necessary, add a field and some data.
Right click on your layer and select properties. In the lable tab, choose your data field and set up options if necessary.