Players who only have access to the 2014 Player’s Handbook will maintain their character options, spells, and magical items in their character sheets. Players with access to the 2024 and 2014 digital Player’s Handbooks can select from both sources when creating new characters.
I don’t have a reference on how it was before, but I tried Beyond once and it was terrible. I cannot in good conscience recommend anyone spending money on such a horrible piece of crap.
I have way more fun filling the character sheet for myself. I use Emmet Bryne’s custom character sheets and the Spells 5e app when I need to reference spells.