“Tape light strips” can be added under kitchen cabinets with minimal effort.
If you already have an outlet under counter somewhere you can “cut in” an additional outlet box to add a switch using something called an “old work” electrical box that you will find in any big box store such as Home Depot or Lowe’s or you can use the existing outlet with a switch / outlet combination.
One item of interest is that you can take a jumper off a dual gang outlet and make one outlet “switched” while the other has constant power. I opted for this solution as it also allowed me to put my home security alarm charger above the cabinet.
Here is an excellent write up I found on the step by step to “cut in” additional outlet boxes. https://www.thespruce.com/install-old-work-electrical-box-1824655
Note: NEC codes call for 20 amp circuits on anything GFCI protected which is basically anything in a kitchen. 20 amp circuits require 12 gauge wire, not 14.
Once you have everything cut in and wired up, you can drop the thin low voltage DC cable between any channels in the cabinets. Usually all cabinets have some sort of channel on their side or where they meet the next cabinet.
Then tape (or hot glue) your LED strips under the cabinet and plug them in to the DC low voltage cable.