depends what range is blocked by the UV blocker and how really the blocker
is good.

range 290nm-315 nm initiates the photoproduction of vitamin D

like with the sunglasses, some producers claim that they block UV radiation
in fact they might only block small percentage of the UV radiation

so there is no way to tell if your UV blocker blocks the 290nm-315 nm  range
without testing

It will reduce it since only 3-4% of the UV will go through.

It's easy and economical to take a 2,000 IU vitamin D tablet.

--
  Ron

im kinda not ready to install film for my car windscreen because of
this reason

many farmers working long hours under the sun does not get skin
cancer, (my own observation of villages in south east asia)