I have a Bachelor degree in physics with very low GPA, but I like to study math and this time aim to get high GPA. I can't afford university fees or cost of living in abroad. I live in Georgia and already used up possibility of financial support for university since I got it for during Bachelor degree in physics.
Would somebody please let me know if there is/are countries that offer Bachelor degree in math esp. with distance learning but for (almost) free tuition? And it doesn't matter how low ranking has that university or where that country is, since I can apply for a better university for Master degree in math after graduation if I get high GPA.

I've never heard of free degrees. You may find teaching jobs that pay for your room and board abroad, and help with tuition to further your education. A good idea would be for you to research this yourself. Why can't you work during the day and take online classes at night?

No, there are no real universities that will provide a free education.

You can, still get student loans if you want to risk the debt. Also, if appears you passed, so why not look at a Masters Degree, and show good grades in it. Why would you want another degree in a closely related field.

Also, perhaps in your field it matters, but I have never, not once in 40 years of working, ever had to tell them my GPA, they just wanted to know if I had a degree or not.