Apart from the dragging that Piotr mentioned. (Try both: d and g. They have different drag behavior).
There is no need to delete & redo. You can simple add the missing section. If tracks are co-linear, KiCad often merges them into a single longer track. But some crud will accumulate over time, this can be cleaned up with PCB Editor / Tools / Cleanup Tracks and Via’s.
I am surprised seeing at your ‘lines’ GND (net identification). I thought they are only at tracks. But last time I have been using KiCad in 2024 and have never been using lines at copper layer. May be lines can also have net (since some KiCad version).
How did you routed with lines? When you start routing (hotkey x) tracks are used, I think.
This was introduced in KiCad V8. Graphic objects can now have net names and be an “official” part of conductive copper. When you start a line from a pad (with [Ctrl + Shift + L]** it automatically gets the net name from that pad, very similar to laying tracks.