how to use joins in find method in models?

You don't use them. You use Model::query or query builder. Find/findFirst is only for finding models in the same class. For joins use other ways or just set relations and use getter for getting related records.

Users::query()
->columns([
'Api\Models\Users.id',
'Api\Models\UserInfo.address'
])
->innerJoin("Api\Models\UserInfo","Api\Models\Users.id = Api\Models\UserInfo.uid")
->execute();

i want to get data of the ids which are present in Users model but not in UserInfo Model...how to write query for this?

Users::query()
->columns([
'Api\Models\Users.id',
'Api\Models\UserInfo.address'
])
->leftJoin("Api\Models\UserInfo","Api\Models\Users.id = Api\Models\UserInfo.uid")
->where('Api\Models\UserInfo.uid IS NULL)
->execute();

How can i get the alias for result obtained..!!