If my husband and i are filing a joint return, and are partners in a business, how do we enter our income and expenses in turbotax standard edition?

The easiest way to do it is through the Forms mode. Create the T2125 - Statement of Business or Professional Activities for the one spouse, with all the amounts split. Then select Edit>Forms>Copy/Transfer Form and click “Copy” to make a copy of the T2125 onto the other spouse’s return. Then you can just edit the 2nd spouse’s form where necessary. The main thing you will have to edit is the partnership second, because on Spouse A the partner will be Spouse B (50%), and vice versa on the other one.