I downloaded Bîtcoin Core on a laptop without knowing it takes up a lot of space and my laptop has only 128 GB disk space. It keeps saying "low disk space" so it won't sync. I sent lots of bitcoins there a while ago and was wondering if there's a way to retrieve them.
I would suggest running bitcoin core in pruned mode if you don't have enough space to for the entire blockchain.
You can start bitcoin with the
-prune=X command line argument or put
prune=X in your conf file, to limit the amount of space used by the blockchain to only X megabytes. It will delete the old blocks and keep only the most recent blocks on your computer.
Related answer: How to free up the space taken by bitcoind?
Alternatively, if you just want to recover your coins, you can backup your wallet file and move it to another computer that has more space for example.
i sent lots of bitcoins there a while ago and wondering if theres a way to retrieve them.
Retrieval isn't the right word. Bitcoin are in the public blockchain that every full node has a copy of. You never actually remove (retrieve) Bitcoin from the blockchain. You just move it from address to address using your private key to prove "ownership".
You can use one of the "blockchain explorer" websites to check the amount of Bitcoin associated with an address for which you (and only you) know the corresponding private key..
If you need to spend the Bitcoin before your Bitcon core has synced, you can stop the Bitcoin core process and install a lightweight wallet instead.
Longer term storage should be in a paper wallet or hardware wallet (or rather at an address associated with a private key that is only in one of those types of wallets.