We usually freeze baguettes. Since they are long, I just toss the whole bread in the freezer, the crust protects the bread. I use microwave to defrost. I’ve tried to freeze certain bread in ziplock bag and find no difference. I don’t recommend slicing before freezing unless you use it in less than 3 weeks or vaccum seal. Even ziplock bag cannot prevent freezer burn on the cut side for longer period.
For croutons or crumbs, I prefer to use a normally defrost bread and proceed than preparing them this way beforehand.
