Best Way to Access an Old Wallet from 2013

How do I make my 2013 wallet usable? I’m on Debian, thinking of compiling Bitcoin Core. Gonna need to sync my full node with 2 laptops one airgapped for cold storage and another online for broadcasting. Super interested in using that new PSBT thing but I’m lost on how to pick specific UTXOs in Coin Control for the file. Any tips without wrecking my wallet.dat?

Just use "File->Restore". That’ll put your wallet in the right folder and load it. Migrating to a descriptor wallet isn’t mandatory, by the way. You should export your addresses or public keys after that, especially if using legacy addresses. You can dump the wallet, but remember to add `addresstype=legacy` in your bitcoin.conf file and restart. You’ll need a watch-only wallet for your online setup too.

What does it mean "loaded"? Like, is it just the standard loading procedure? If I gotta export keys, why is that step necessary? I thought loading would get me everything I need. Am I missing something? So, is "File->Restore" seriously all I have to do to be good with private keys?

Yeah, nc50lc meant restoring the wallet.dat file. When you restore, you copy that file to the wallets folder in Bitcoin Core. What gets loaded is your wallet itself. For your online laptop, you'll have to import the descriptors of the public keys using importdescriptors to set up a watch-only wallet. It gives more flexibility for signing PSBT transactions, hence the suggestion to create a new wallet without private keys.

It’s a bit complicated, having to juggle offline and online machines while doing the PSBT process. You need that watch-only setup online and the one with private keys offline. But if you want an easier way and don’t need total privacy, go with Electrum. Just select "Import Bitcoin Addresses or Private Keys" while setting the watch-only wallet up, add your addresses, and you’re almost done.