Only Desktop and Document icons on my sidebar are shown with blue color, how can I fix other icons which are not showing blue color?
You’re running Big Sur. When Big Sur was released, a number of changes had to be made to TotalFInder and the loss of the colored Sidebar icons was lost. Unfortunately, with all the changes Apple is making in the software, the update to the icons isn’t very high priority.
No im running catalina
You can get a truly colored sidebar from MacEnhance/MacForge. It’s called ColorfulSidebarX and it works perfectly on Catalina. I haven’t tried it on BigSur, but it’s supposed to work on BigSur too!!!