Why my sqaush vine is turning yellow from the base and leaves are turning yellow.
Squash are, unfortunately, not all-season-long crop plants - they tend to peter-out partway through the season and should be removed when no longer fruiting well. Aging leaves are also likely to show signs of ailments like fungal infections, though they are not worth treating with fungicides (plus, they may not work this late in the season and they won't cure existing issues). Yellowing, drying, and shedding of a plant's oldest leaves over time is normal, but may be exacerbated by stressful growing conditions (too wet, too dry, not enough nutrition, too shady, high heat). For aesthetics as well as disease prevention, it's advisable to remove such leaves as they appear.
The "-tone" fertilizer line is fine for this use but is not a quick-release fertilizer, so results from an application may take over a week to be evident; possibly more. It will not reverse lower-leaf yellowing but should cause new growth to be a richer green color, and possibly trigger more new growth outright as well. If it has had no impact, roots are either not able to absorb the nutrients due to poor health or soil conditions or the nutrients were not sufficiently limiting to growth in the first place - another factor was limiting the plant's performance like the stressful conditions mentioned above.
If you are not getting a reliable harvest and the plant is declining, we suggest removing it entirely instead of worrying about clean-up, fertilizing, or any treatments. This will also free-up space if you wish to plant any fall vegetable crops.