Please read carefully and follow the proper steps that I have mentioned below to fix this CORS issue.
Step 1
Firstly create a proxy.conf.json
file in the src
folder in your angular application.

Step 2
Now we have to create the proxy configuration for API endpoints. So add your proxy configuration in your proxy.conf.json
file as given in the below format-

Definition of parameters is given below-
1. "/echo
” is your API Path.
2. "target"
is your domain name where your API’s are hosted.
3. "secure"
is boolean type parameter, if your domain has SSL then you should use true else you should use false as value.
4. "changeOrigin"
should be true if your backend is not hosted on localhost server.
5. “logLevel"
is used to check whether proxy is working or not. Proxy log levels are info (the default), debug, warn, error, and silent.
Step 3
Now you have to put proxy.conf.json
path in proxyConfig
option in angular.json file just like mentioned below.

Step 4
Now finally we have to update our API path in our service file. Before Proxy we were using https://reqbin.com/echo/get/json
URL. But now we do not want to write domain name here in URL because we have already configured domain name https://reqbin.com
for the route of "/echo"
in our proxy.conf.json
file.

Step 5
Finally, you have to restart your project with the ng server
command and if we look at the Chrome Dev Tools network tab, we can see that the request came from http://localhost:4200/echo/get/json

And we will see that the API is working on local environment using Proxy config and CORS error has also gone.
Note: This is just a fix for development. If you have CORS issue in production, the problem likely has to do with the server configuration!