It's possible that when you first set up the wallet you chose Simple Mode (bootstrap) or Advanced Mode, both of which require downloading the blockchain to your computer. If so, there is a Simple Mode (without bootstrap) that instead of downloading the blockchain, connects to a remote node, allowing you access to your funds almost instantaneously. It should be noted that this may compromise some aspects of your privacy. The remote node will have access to your IP address for example (unless you're using a VPN or ToR).
To check your wallet mode, go to
Info and see
If you are not in Simple Mode, and are happy to accept the trade-offs that come with using a remote node, you can switch your wallet mode.
If your wallet is open, you need to close it first. Go to
Close this wallet:
The main menu (Welcome to Monero screen) will open. At the bottom left, click on Change wallet mode button, and on the next page select Simple Mode. Next, open your wallet file again.
The wallet should automatically connect to a remote mode and show your balance, but in the event it doesn't there's info on how to find a remote public node in the guide on getmonero.org: https://www.getmonero.org/tr/resources/user-guides/remote_node_gui.html