Unable to resolve dependency tree error when installing npm packages

When trying to install the npm packages using npm i command, I am getting the following exception:

npm ERR! code ERESOLVE
npm ERR! ERESOLVE unable to resolve dependency tree
npm ERR!
npm ERR! While resolving: gf-kautomata-pipeline-ui@0.0.0
npm ERR! Found: @angular/core@9.1.12
npm ERR! node_modules/@angular/core
npm ERR!   @angular/core@"^9.1.4" from the root project
npm ERR!
npm ERR! Could not resolve dependency:
npm ERR! peer @angular/core@"7.2.16" from @angular/http@7.2.16
npm ERR! node_modules/@angular/http
npm ERR!   @angular/http@"^7.2.11" from the root project
npm ERR!
npm ERR! Fix the upstream dependency conflict, or retry
npm ERR! this command with --force, or --legacy-peer-deps
npm ERR! to accept an incorrect (and potentially broken) dependency resolution.

I have tried reinstalling the Node.js package and setting the proxy to off using:

set HTTP_PROXY=
set HTTPS_PROXY=

The issue is still there. What I am doing wrong?

Update:

When I run the following command:

npm install --legacy-peer-deps

The following error is displayed:

npm ERR! code ETARGET
npm ERR! notarget No matching version found for @angular/http@^9.1.4.
npm ERR! notarget In most cases you or one of your dependencies are requesting
npm ERR! notarget a package version that doesn't exist.

npm ERR! A complete log of this run can be found in:

This is not related to an HTTP proxy.

You have dependency conflict (incorrect and potentially broken dependency) as it says, so try to run the command with --force, or --legacy-peer-deps. If it doesn't take effect, the temporary solution is using prior versions of the Node.js (downgrading the Node.js version) as it causes this kind of errors to happen sometimes.

Update based on the OP's update:

As you see, it fires the following error:

No matching version found for @angular/http@^9.1.4.

Take a look at angular/http page. Note that the latest version for that deprecated package is 7.2.16 while you request an upper version (e.g., ^9.1.4)! So, try to check the project dependencies and follow the raised errors in order to solve the problem.

Stack Overflow Q#64573177, score: 892