I no longer know much about futures but open interest is the same in both the futures and options markets.
Open interest represents the number of contracts that exist on any given day. There are 4 scenarios:
(1) BTO and STO = Both parties are initiating a new position (one new buyer and one new seller) so open interest increases by one contract
(2) BTC and STC = Both parties are closing an existing position (one previous buyer and one previous seller) so open interest declines by one contract.
(3) STC and BTO = If a contract owner sells to a new trader, open interest does not change.
(4) BTC and STO = If someone short a contract buys from a new trader, open interest does not change.
(1) creates a new contract
(2) a contract ceases to exist
(3) and (4) the contract is just changing hands
In all cases, there is a buyer for a seller, each with an opposing view. In isolation, this tells you nothing about market direction.
Total volume doesn't move price. Net excess buying volume moves price up and net excess selling volume moves price down.
With options, a call buyer is bullish. If that call purchase is to hedge a short position in the underlying, the trader is actually bearish. There's no way to infer what their bias is from just seeing the call purchase and possible change in open interest. To that end, some delve into combining price, volume and open interest to determine direction. I've never been able to discern it but here's an article from Investopedia that explains it.