IPFS is a free and open protocol - using the software itself is free. However you still need a strategy to persist content that you are adding to the network. If you already have hardware that you can run an IPFS node on (like your personal computer/internet), there aren’t additional costs over normal bandwidth usage - however you can also explore other hosting options like Pinata (https://pinata.cloud/), Infura (https://infura.io/), etc.
Do you have a walkthrough or getting started guide you are following? Any other details about your exact steps to add a file to IPFS (are you using a go ipfs deamon? ipfs companion? ipfs desktop? something else?) and how you are trying to retrieve it (ex when trying to retrieve from the same peer). More info will help us pinpoint where any issue might lie and point you in the right direction!