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to install pip i needed python 3 because i had errors with python 2 so i changed the symlink of python -> python 2 to python -> python 3 and now i no longer can use yum. Yum has been uninstalled and i don't know what to do i am a beginner.

I changed Python symlink which was

lrwxrwxrwx 1 root root 7 Apr 3 15:10 /usr/bin/python -> python2

to

lrwxrwxrwx 1 root root 7 Apr 3 15:10 /usr/bin/python -> /usr/bin/python3

with the command

$ sudo ln -sf /usr/bin/python3 /usr/bin/python"

Because i needed python version =>3 to install pip.

I already tried to put the symlink back as it was before with python2 but it doesn't change anything yum has been desinstalled i don't know how.

When i try to do:

$ sudo yum update

sudo: yum: command not found or $ whereis yum yum: /etc/yum or $ rpm -q yum package yum is not installed

I tried that:

$ sudo rpm -ivh yum-3.4.3-168.el7.centos.noarch.rpm yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch.rpm

Now yum is recognized but i always get an error (see screenshots).

I don't know how to solve the problem, please if someone could help me it would be nice of you.