Both mean to walk. "Andar" is used mostly in Spain, "Caminar" in Latin America. Both would still be understood, but for example in Latin America, "andar" is considered more poetic or metaphorical.

And just to confuse things a little more there is also "pasear", which means roughly "to go for a walk".

I heard that 'andar' is more like 'to go for a stroll' whereas 'caminar' is simply 'to walk'. Also, FYI andar can be used to mean 'ride', ex. I want to ride a horse 'Quiero andar a caballo'.

The sentence needs a semi-colon between well and I.

This really is two sentences or one sentence that needs a semi-colon. I do call that a run-on sentence.

I notice a great many examples in Spanish, both in the exercises and on the discussion board, which would be considered a run-on sentence (or in need of a semicolon) in English. (But then, people generally do write very casually on internet forums and consider punctuation optional. So it's the examples in the practice sentences I wonder about more.) I'm holding out until I'm actually reading Spanish literature to see what flies (another figurative use of motion verbs!) by actual standards.

Because "Estoy bueno" would mean "I am good" (a good person). And in some Latin American cultures, "I am hot" (i.e. sexy, not temperature).

They both mean "I am" but "estoy is used to talk about your condition or location, and "soy" is used to talk about who you are. Examples:

Estoy: I am happy. I am tired. I am in the garden.

Soy: I am a teacher. I am tall. I am a Canadian.

For more information, look up Ser and Estar in a grammar book.

it can be used but i mean this whole application is like proper spain spanish not spanish from other countries

Why would you say I find myself well instead of I am well?

Duo generally doesn't like it when you reverse the expression like that, in large part because it can subtly change the meaning of the sentence: there's almost always a slight emphasis on the first part, as compared to the rest.

For example, picture the difference between "I had cake yesterday," and "Yesterday I had cake." The first sentence places the importance on the cake, while the second one emphasizes that it happened yesterday.

Similarly, Estoy bien, puedo caminar means, "I am well, [so] I can walk," while Puedo caminar, estoy bien is more like, "[Since] I can walk, I am [doing] well."

I hope this helps.

It's the difference between ser and estar. Like the difference between por and para. A peculiarity of the language. Personally, I try to do enough examples that the usage I choose isn't defined by a list of right or wrong but rather the sense that his word "sounds right" in a given situation. The very short form of the answer is that ser is about permanent things and estar is about temporary things, so health/emotional state is "estar". "Soy bien" sounds like you are saying that you are a person of good character. "Estoy bien" means "I am feeling ok" (which isn't necessarily permanent, to be sure).