Using 1.3, how do I "save tiles" even after deleting them? Also, how to make/keep both 16x16 and 48x48 tiles?

[SwordSorcery2020]

I am not sure if the latter, larger tiles are 48x48 or 64x64

Nor am I sure if I can make 48x48 and 64x64 tiles that aren’t confused to be smaller 16x16 ones