I was trying to install react router when my vscode terminal showed some issues so I used npm audit fix --force after which it just showed more issues. I've deleted node-modules and reinstalled but its still the same thing. Now the app page is displaying this.

To clear the cache present in npm, you need to run the command. If it doesn't work, run the force clean method since the cache is not cleared simply. See the below command.
npm cache clean --force
The clean command show above clears all the data present in your cache folder. To verify whether your cache is cleared or not, you need to use the below command.
npm cache verify
After that run the installation command.