"Although I was tired" is a dependent clause because it begins with a subordinating conjunction (although) and cannot stand alone as a complete sentence.
It needs an independent clause to complete its meaning (e.g., Although I was tired, I finished my work.)
"I am staying inside" is a complete sentence with subject and verb, expressing a full thought — this makes it an independent clause.
A dependent clause cannot stand alone and usually begins with words like because, if, although, etc. The part "because it is raining" is the dependent clause here.
