Hey farhan, as i recognized your issue is in authentication part , follow this steps to solve it :
make a key pair
First, Log in to the computer you’ll use for accessing the remote host, and use the command line SSH to generate a key pair by the RSA algorithm. To generate RSA keys, type the following on the command line, and click on enter:
ssh-keygen -t rsa
Supply a filename and password
You will have to give a filename to save the key pair and a password to protect your private key. If you want to continue with the default filename and location for your key pair, click on Enter or Return without entering a filename. Alternatively, you can enter a filename such as My_ssh_key at the prompt and press Enter or Return. Pay attention that many remote hosts are configured to accept private keys with the default filename and path. Therefore, you must explicitly invoke this on the SSH command line or in an SSH client configuration file (~/.ssh/config).
You need to enter a password with at least five characters and click Enter or Return. If you click on Enter without a password, it will generate your private key without password protection.
Copy public key
Use SFTP or SCP for copying the public key file to your account on the remote system.
Enter your account credentials
Your public key will be duplicated to your home directory and kept with the same filename on the remote system.
Log in to the remote system with your account username and password
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