visual studio not showing me red lines

my visual studio isnt showing red lines for some reason. im new into programming so i dont know where im failing my code, red lines helped me a lot. anyone knows how to fix this

 

By red lines, you mean underlined text?
when last time your VS worked. What have you changed? Which VS version you have? Which Unity version you have?

 

yes, the red squiggly lines that appear when you type something wrong
i formatted my disk 2 days ago, but only started with unity today again
i installed version 2.1f with the same visual studio i had before. the 2017 version
i tried 2019 but there's no red lines as well, and it's more confusing since there is no blue
text for variables or light blue for variable types.

 

Try reinstall VS, or Unity.
The installation order of VS - Unity may have importance. For example, if you installed Unity before VS and all relevant packages. Just a guess however.