このエラーメッセージに関する原因と対処に関して説明します。
エラーメッセージ(英語)：
linux pip not found
対処
関連リンク
EC2(Amazon linux)でpipインストール時のエラー対処 - Qiita
https://qiita.com/suzukihi724/items/5a249ee70104d9799ac1
Linux で Python、pip、EB CLI をインストールする - AWS Elastic Beanstalk
https://docs.aws.amazon.com/ja_jp/elasticbeanstalk/latest/dg/eb-cli3-install-linux.html
Install the AWS CLI on Linux - AWS Command Line Interface
https://docs.aws.amazon.com/cli/latest/userguide/install-linux.html
Upgrade pip in Amazon Linux - Stack Overflow
https://stackoverflow.com/questions/34103119/upgrade-pip-in-amazon-linux
how to install pip with yum on EC2
https://stackoverflow.com/questions/45073617/how-to-install-pip-with-yum-on-ec2
pip broken, reinstall doesn't work. EC2
https://stackoverflow.com/questions/34734436/pip-broken-reinstall-doesnt-work-ec2
error when "sudo pip" on an AWS ec2 instance
https://stackoverflow.com/questions/40697310/error-when-sudo-pip-on-an-aws-ec2-instance
bash: pip: command not found
https://stackoverflow.com/questions/9780717/bash-pip-command-not-found
Error : sudo: pip: command not found by - Linux Academy
https://linuxacademy.com/community/posts/show/topic/28462-error-sudo-pip-command-not-found
python pip エラー - Amazon Linuxでアップグレードピップ - CODE Q&A ...
https://code.i-harness.com/ja/q/2085f4f