Beyond means on the far side of. It is a preposition.
- The house is beyond the bridge.
- We will be safe when we get beyond the river.
Beyond can also mean exceeding, out of reach of and similar ideas.
- Your work is beyond all praise. (= too good to describe adequately)
- He is living beyond his income. (= He spends more than he earns.)
- This problem is beyond me. (= I can’t solve this problem.)
When beyond refers to time it means after.
- I cannot stay with you beyond Tuesday.