Need software for a retail store free simple?

Question

Software and Internet Services

Good afternoon IT specialists Habr.
I'm looking for a simple checkout software for a store, not online, no cashiers, etc.
There is a business I would like to optimize and simplify it.
PS The software should be free, I understand that you have to pay, but I'm going to buy faces. as soon as I’m in +
Thank you for reading my stupid question, I can reward those who help, I used such a program in 2015-16, but right now I didn’t find this program and yes, I DO NOT need checks and Federal Law 54 or what kind of law I don’t live in RF.

Answer 1

Excel / Libreoffice calc / Gnucash

Answer 2

the question is not posed correctly, why the software, what functions it should have, what it should do, so there are plenty of free ones in the open spaces, you just need to search and understand yourself or explain to people what you need only normally