Where do I start with learning geography and countries

I am very bad at geography. I want to learn all of the countries in the world, and then their locations and flags. I’ve heard of sporcle but the website is very slow (I’m on iOS) and it’s quizzing me on all the countries, but I don’t know them. I know a lot of countries but I want to learn ALL of them and their names. I heard a lot about an app called Seterra but upon looking at reviews I see a lot about incorrectly matched flags, biased information, etc…a lot of posts I’ve found online were also old…does anyone know an app or a method to start LEARNING the countries, names and locations? That’s up to date and unbiased? I’m just pretty lost on how to start.