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Let's learn the basic tags in order.
Literal
Order [object-を] following [and-て] basic-[attributive-な] tags [object-を] learn-[continue-ていく][volitional-よう].
Tutorial or textbook register — likely introducing HTML tags. 順を追って ('following the order, in sequence, step by step') is a common adverbial. 覚えていく ('keep learning, progressively learn') uses ~ていく to mark the learning as continuing forward through time. The ~よう volitional 'let's X' frames it as a shared endeavor with the reader.