Look up how to can something like home made pasta sauce with tomatoes. That was the first thing I ever tried, along with bramble jam. Basically, you clean used empty glass jars and their lids (lids need to ideally be the ones with the 'pop' button in the centre), then fill them with the hot contents, close the lid, stick them in boiling water for a bit to make sure the whole thing has boiled, take them out and place them upside down to cool down.Water canning is something I'm aware of but no actual experience so would be good to learn myself.
As they cool, if they seal well, the lid gets suction as indicated by the press-button in the centre.
The real skill is knowing what can be safely preserved that way, and what requires pressure-canning instead.
The US FDA publishes a pretty good book, I think it is free to download.

