Character packs contain the characters/items from the relevant book pre-entered in HD format. They are not necessary — you can enter everything on your own into HD if you so choose...or only enter those items that you decide you want to copy out of the books, etc.
HD itself will give you everything you need to create characters, items, etc. in accordance with the rules of the system (either 5E or 6E). It is not a replacement for said rules — you’ll still need to know the system in order to know what HD is doing, how it’s calculating points, etc.
As for examples of the character sheet, HD uses an export format which allows for moderately free customization of the character sheet output. You’ll find a number of examples in the Downloads section of this site.