TexLive 2020 installation Ubuntu

I just installed TexLive 2020 into my Ubuntu laptop following the steps written in: http://www.tug.org/texlive/quickinstall.html

However, when I arrive to the steps

Post-install: setting PATH

After the installation finishes, you must add the directory of TeX Live binaries to your PATH—except on Windows, where the installer takes care of this. For example: PATH=/usr/local/texlive/2020/bin/x86_64-linux:$PATH Use the syntax for your shell, your installation directory, and your binary platform name instead of x86_64-linux.

I get lost. I run the command line PATH=/usr/local/texlive/2020/bin/x86_64-linux:$PATH and nothing happens. I have as well TexLive 2017 installed in my laptop, but when I try with a test document, some packages like raleway are not installed.
I am obviously missing some steps in the PATH part. What am I suppose to do there?