Upgrade angular application from 6 to 10 produces lots of errors after update

Question

Kindly suggest the best way to upgrade my application also share how to resolve peer dependency issues like this :-

Package "ngx-chips" has an incompatible peer dependency to "@angular/animations" (requires "^8.0.0" (extended), would install "10.0.7").
Package "@ng-bootstrap/ng-bootstrap" has a missing peer dependency of "@angular/localize" @ "^10.0.0".
Package "@ng-idle/core" has an incompatible peer dependency to "@angular/common" (requires "^9.0.0", would install "10.0.7")
Package "@ng-idle/core" has an incompatible peer dependency to "@angular/core" (requires "^9.0.0", would install "10.0.7")
Package "@ng-idle/core" has an incompatible peer dependency to "tslib" (requires "^1.10.0", would install "2.0.0")
Package "@ng-idle/keepalive" has an incompatible peer dependency to "@angular/common" (requires "^9.0.0", would install "10.0.7")
Package "@ng-idle/keepalive" has an incompatible peer dependency to "@angular/core" (requires "^9.0.0", would install "10.0.7")
Package "@ng-idle/keepalive" has an incompatible peer dependency to "tslib" (requires "^1.10.0", would install "2.0.0")
Package "ng2-file-drop" has an incompatible peer dependency to "core-js" (requires "^2.4.1", would install "3.6.5").
Package "@ng-select/ng-select" has an incompatible peer dependency to "@angular/common" (requires ">=9.0.0 <10.0.0", would install "10.0.7")
Package "@ng-select/ng-select" has an incompatible peer dependency to "@angular/core" (requires ">=9.0.0 <10.0.0", would install "10.0.7")
Package "@ng-select/ng-select" has an incompatible peer dependency to "@angular/forms" (requires ">=9.0.0 <10.0.0", would install "10.0.7")
Package "ng-recaptcha" has an incompatible peer dependency to "@angular/core" (requires "^6.0.0 || ^7.0.0 || ^8.0.0", would install "10.0.7")
Package "copy-webpack-plugin" has a missing peer dependency of "webpack" @ "^4.37.0 || ^5.0.0".
Package "ngx-mask" has an incompatible peer dependency to "@angular/common" (requires "^9.1.0", would install "10.0.7")
Package "ngx-mask" has an incompatible peer dependency to "@angular/core" (requires "^9.1.0", would install "

Answer 1

When upgrading your Angular project, moving across multiple major versions is not recommended. I strongly suggest you follow the steps using the update guide here : https://update.angular.io/.