I found that as a wizard I can buy spells and copy them into my book and know them. There is no way to use this feature on dnd beyond accurately. The way I’ve been is either writing it down on a piece of paper or on my character sheet in “other”. I would like there to be a way to do this on Dnd Beyond it self on  the spell list. I can do it with a feat but then it is always prepared. 

thank you 

Manage Spells

Add Spells 

When Added, you can use Manage Spells and Spellbook to prepare them. 

O.o

Feature is fully implemented.

Not true. Cantrips and level 1 spells work fine but nothing shows up for level 2 or higher. I have a wizard that has 4 level 1 slots and 3 level 2 slots but can't add anything beyond 1st level spells. Is there something that needs unlocking besides the PHB and DMG?

Quote from KairedanDragonsbane >>

Not true. Cantrips and level 1 spells work fine but nothing shows up for level 2 or higher. I have a wizard that has 4 level 1 slots and 3 level 2 slots but can't add anything beyond 1st level spells. Is there something that needs unlocking besides the PHB and DMG?

 
No it is very and completely true. And no, you don't need to unlock anything. 

Here's a video.

I'm also going to add, just in case, your ability to add to spellbook and prepare wizard spells is based on your wizard level, not what slots you have. This is worth noting in the case of Multiclassing. 

Even if you had 9th level slots due to multiclassing - if you're a 2nd level wizard, you can only learn/scribe or prepare 1st level spells. 

Yeah, was getting wound up on the character sheet was showing me I should have 2nd level spells available. However the video didn't answer the question, still couldn't add higher level spells even when I tweaked the character level. This doesn't seem to be workable from the character sheet. I did go all the way back to the builder and added spells from there. So yes it works, just not as transparent as a new user would think it would be.

Quote from KairedanDragonsbane >>

Yeah, was getting wound up on the character sheet was showing me I should have 2nd level spells available. However the video didn't answer the question, still couldn't add higher level spells even when I tweaked the character level. This doesn't seem to be workable from the character sheet. I did go all the way back to the builder and added spells from there. So yes it works, just not as transparent as a new user would think it would be.

 
Watching the full video may help, because, yes you can do that from your character sheet. 

Can you post the link to your character, perhaps?