Nechoma, as someone who has been studying halacha my entire life and teaching it for several years, I can tell you that it takes many, many, years of studying halacha in order to know all the basic halachos that you need to know on a daily basis.
I attended a Bais Yaakov high school and know many others who have and I do not know a single person who knows all of the halachos that one needs to know on a daily basis.
I have known very-seriously-Frum Bais Yaakov graduates from very-seriously-Frum families who were not aware of and were oiver on basic halachos such as cutting up a salad on Shabbos several hours before the meal and speaking about melachos that they were going to perform during the week.
To take one (very important) example, I know very few people (men or women) who know all of the halachos of dibbur chol on Shabbos and people (including Bnei Torah) are oveir on it all of the time without even realizing it.
To take another example: I taught Hilchos Brachos last year, and I studied it in depth, and I realized that there are many, many halachos that people are not aware of. For example, most people (of both genders including B’nei Torah) think that if you have a Haetz and a Haadamah, you make the bracha on the Haetz first, and this is incorrect according to the Mishna Berurah and most comtemporary Poskim.