-Does this mean we effectively would be running as a Partnership rather than a Corporation so we would withdraw funds from the business account as and when we choose to our personal accounts. Overall tax would then be calculated at the end of the year on a personal basis through a personal tax return rather than a corporation return?
An LLC with more than one member is a Partnership.
A partnership must file an annual information return to report the income, deductions, gains, losses, etc., from its operations, but it does not pay income tax. Instead, it "passes through" any profits or losses to its partners. Each partner includes his or her share of the partnership's income or loss on his or her tax return.
Partners are not employees and should not be issued a Form W-2. The partnership must furnish copies of Schedule K-1 (Form 1065) to the partners by the date Form 1065 is required to be filed, including extensions.
You started out by asking about an LLC and the important part is how many members. One is a sole proprietor while 2 or more is a partnership.
This would be a US partnership so yes, all partners are subject to US tax and reporting on their share.
The tax is withheld by the partnership (whoever does the accounting). He has to get a tax number (an ITIN).
It does not matter that he is not a US citizen. An ITIN is for those that have a US tax reporting obligation but cannot be issued an SSN.