If the company reimburses you: Dr. Office Supplies and Cr. Cash.If the company does not reimburse you: Dr. Office Supplies and Cr. Accounts Payable - Owner (if you will eventually be reimbursed) or...
Most likely yes, because office supplies usually last long timer, e.g. binders, file holders. You just need to purchase some consumable supplies regularly like pens and markers, but that won't cost...