I am using Angular 13,and as you can see from the pictures above,I have already imported the correct custom css and js files in angular.json, however whenever I try to separate components from index.html to app component.html the sidebar stops working

I've had this problem for 2 weeks now and it's stopping me from completing my full stack project, if anyone can be of any help I'd be forever grateful and if you need more details and info I'll update the post

thank you