You will need to perform a clean install (back up your data first). After installing LTSC, you can apply cumulative updates normally even with 512MB VRAM.
, the first thing you need to know is that VRAM is physical hardware on your graphics card. You cannot download more of it any more than you could download a larger hard drive. However, if you are stuck with gpu vram 512mb download windows 10 upd
The /quiet switch suppresses most GUI elements. The /compat ignorewarning forces the installer to ignore low VRAM warnings. The update will run silently in the background with minimal GPU usage. You will need to perform a clean install