Informally yes, but the scientific way is to use a ring infiltrometer: https://www.fao.org/3/s8684e/s8684e0a.htm -- Basically instead of digging a hole, you pound a pipe into the ground and then fill the pipe with water.
As for agricultural practices being able to change soil composition multiple feet down, trees and tap-rooted plants are very effective at placing large volumes of organic matter at depth. One example, Lacy Phacelia (Phacelia tanacetifolia) is an annual plant that produces a dense fibrous root system that reaches a depth of 4 feet; in the fall the Phacelia plants die, and their roots decompose at depth, creating pathways for water infiltration while also increasing soil organic matter at depth. The same goes with other trees and shrubs. The farmer from the "It ain't much but it's honest work" meme, Dave Brandt, has some really enjoyable presentations on youtube about improving soil composition at depth.
How do you know that?
How deep do roots go? Do worms dig? Do you know?
I do not. But I am not making assumptions
I went to check the above sentence, and the first hit was this detailed article from Washington State, which analyses Brown's claims in detail, and explains why the scientific community is skeptical of them:
https://csanr.wsu.edu/regen-ag-solid-principles-extraordinar...
Anyway, even if, as Gabe Brown claims, regenerative agriculture is an order of magnitude more effective than expected, and you applied it to 100% of the land in Pakistan, it would still only reduce flooding by less than a foot.