Does karma force things to happen? I know karma matures with the right conditions but does it ever force things to happen with the certainty that it will happen?

Like for example can earning a specific karma say that it's going to force an effect, like when somebody does something good that means they'll become a private buddha in the future. Does it sort of "force" or push things in the direction of the karma to happen or is it still just waiting for the right conditions.
It doesn't force things to happen because karma by definition has no self which can force anything.
Karma doesn't really exist as some punishing entity (like a Western God), which is what the word "force" implies in your question.

In Buddhism and Hinduism, the chain of causation that binds beings to the Wheel of Birth and the natural conditions that stem from it, creates a torrent of karma all of which must be satisfied in life after life until samadhi/bodhi can be achieved.

"Conditions" can be anything by the way. A condition can be being in a certain situation, seeing a certain characteristic of a person (e.g. maleness, femaleness), or even "having a body". Oftentimes I believe that karma has an effect that is beyond time, simultaneously immediate, near, and far..