What was mixed in with that manure?
You may have a bin of aged manure if there was nothing much more then manure in there but if there was 1 part manure to 3 parts vegetative waste you could have some compost.
The manure could be spread on a planting bed, although it would be better if 3 times as much vegetative waste was added at that time if all there is is manure.

A compost bin should always have holes in it to allow air in and drainage to escape. A perfectly balanced pile with the right moisture and air can become compost in several months with a couple of turnings. You may or may not have compost yet. If it was mixed with some bedding like sawdust or wood chips, it may have done just fine.

Dump it out and look at it and smell it. If it's very wet and smells bad, it needs to be mixed with some browns (dried leaves, shredded paper, straw, sawdust) and allowed to finish in a pile.

If there was bedding and you still see a lot of that (sawdust or straw etc.), mix with some greens (grass clippings, kitchen scraps etc.), moisten and pile up to continue composting.

If it seems crumbly and looks and smells like compost (earthy rather than poopy), dig it into the garden. It only takes a few months for the bad bacteria to dissipate and you're already beyond that, if it had enough air supply.

I've planted transplants directly in fresh horse manure and they've flourished.

Just put some of the manure in a pot and stick a some transplants in it. Your plants will tell you if its good for them.