External SSD and swap

I have an SSD attached to a rpi4, but new apps being installed are being installed onthe micro SD, how to move all the apps and its files to the SSD.
My rpi4 has only 2GB of ram, and yesterday with some heavy tasks it was full and also the swap memory, currently there’s 1GB of ram. I would like to add more and make the swap on the SSD( I suppose it will better this way).

The easiest way is to make and download a backup, of your current setup, then install FreedomBox on your SSD following these instructions.
Once your SSD setup is up and running, you can use your backup file to restore your apps from the previous setup. Please note that Tiny Tiny RSS has an issue with the backup process, so I’d advise you don’t select it during the backup process.

Thank for your answer, from what I understand following those instructions to install FB on the SSD, the micro SD won’t be needed anymore. My idea was to have the OS on the micro SD, and all the apps files and etc on the SSD, more or less like how Umbrel works. Is it possible? The advantage in my view is that if something goes wrong, one can just reflash the FB image, while keeping the apps and files untouched.

Yes, the SD card won’t be needed anymore.

My idea was to have the OS on the micro SD, and all the apps files and etc on the SSD, more or less like how Umbrel works. Is it possible?

It’s not possible, but even if it was, I wouldn’t go for it.
The most common reason why things go wrong is because of SD card corruption. By switching to an SSD, you eliminate that, plus your box’s performance will speed up significantly.

What you can do is save your periodic backups to a remote machine via SSH or synchronize the backup location with one or more machines using Syncthing.