There's a chance that he knowingly took, But it's just as likely that he already had them while he was vice president which is not uncommon for people in that position, And simply neglected to return them. Still not a good look either way. With the number of documents that were found, it's gross negligence at best, but negligence is almost never prosecuted in cases like this, unless there is some factor that clearly placed the documents in danger of falling into the wrong hands.
For example trump face scrutiny on the fact that he had the documents on his property in an unlocked broom closet, Wish was fully accessible by his entire staff at Mar a Lago. The documents that were in Biden's garage which fall under the same category since the garage Wouldn't fall under a secure place. But the documents found in his office and in other areas that were locked and secured probably won't face any issues.