Best way to save these chilies?

This is probably too late, but absolutely freeze them. I always buy some and use 1, then throw the rest in the freezer to keep for whenever I need some. Lasts me for months, no issue. Don't even need to defrost them before using!

Too late now, but most grocery stores will break down larger packages of produce to sell you the amount you want. Publix does this in Florida, not only for produce, but in their bakery, too. If for instance, you only want two rolls and not the eight in the package, they will be glad to bag up and sell you the two.

You could dry them and/or pickle them. I’ve never dried them before (that I can remember) but I did a quick google search and it sounds pretty straightforward - put ‘em in a dry place and let ‘em dry. As for pickling, you can keep it simple with the vinegar of your choice (I would probably use rice wine vinegar), salt and sugar, or you can add spices as you like (I like adding mustard seed to hot pickled peppers). Delicious in all sorts of salads, sandwiches, etc.

I freeze fresh chillies too. Just put them in tightly sealed container or they'll dry out. Usually still good for 3-4 months.