I'm not familiar with that particular chain, but if it's of similar vintage as the bike - well, there were no quick links then. Only thing like quick links was the master link on BMX bikes and other one speeds that used an 1/8" chain. Chains were taken on and off all the time using the normal link. That was the only way to do it.

It will help if you can get someone to show you how to do it properly. It isn't rocket science, but no longer a common task, at least not the putting it back together part. As previously mentioned, don't push the pin all the way out when you take it off. Also, take care not to distort the outer plate when pushing it back. If you start to bend the plate when the pin is starting to engage, that link is ruined.

here's a basic tutorial: https://www.instructables.com/id/Usi...ke-Chain-Tool/

If you're more comfortable with a modern chain with a quicklink, use one. Chains are disposable/consumables anyway, and it's not a bad practice to replace regularly.