For general confusion:
* Clear
* Certain
* Sure
* Understanding
* Comprehended
* Enlightened
For confusion due to being lost or disoriented:
* Oriented
* Found
* Aware
* Collected
For confusion due to being unclear or ambiguous:
* Precise
* Distinct
* Definitive
* Straightforward
* Unambiguous
For confusion due to being muddled or disorganized:
* Organized
* Structured
* Rational
* Logical
* Clear-headed
The best opposite for "confused" will depend on the specific context and what you're trying to convey.