Not quite sure what your husband is wanting to do. There isn’t a Cherokee project, but there is a Native Americans project which he can request to join if he’s interested in improving Native American profiles by responding to this G2G message: https://www.wikitree.com/g2g/566495/are-you-interested-in-native-american-tribes-people-history#q566495
He can add tags of “Cherokee” and “Native_Americans” to his profile. That way he’ll see G2G messages with those tags. If he is a Cherokee citizen or has ancestors who were, then he can add
{{Native American|tribe=Cherokee}} to their profiles. (That’s a pipe, not the letter L between American and tribe)
Projects only manage or protect a few profiles, usually early people who are subject to myths and/or who seem to collect extra parents and children.