cat: create/write file

Create file without replacing variables:

cat <<'EOF' > /path/file
============================
My name is ${0}
I was input via user data
============================
EOF

cat <<'EOF' > /path/file

============================

My name is ${0}

I was input via user data

============================

EOF

If you check /path/file you will see exactly the content above.
Create file REPLACING the variables while creating:

cat <<EOF > /path/file
============================
My name is ${0}
I was input via user data
============================
EOF

cat <<EOF > /path/file

============================

My name is ${0}

I was input via user data

============================

EOF

In this example, the variable ${0} will be replaced during the creation of the file, hence the content will display your username.

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