@SuperDicq @Archivist >just do the following:
Just adding a LICENSE file legally doesn't mean much.

To license your software correctly, you need to add a license header to each nontrivial file (this is true of any license, not just the GPLv3);
<one line to give the program's name and a brief idea of what it does.>
Copyright (C) <year> <name of author>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or (at
your option) any later version.

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.


You don't need to set the repo to "public" - you can choose to only share the repo to people who purchase a copy of the software under section 6d.