Take a look here for information on VAT.
Assuming you will be standard rated if and when you register for VAT, you will charge your customers VAT at 20% on the value of the invoice assuming the service or good you sell is standard rated for VAT. So, if you sell something for £100.00, you will charge output VAT (A) of £20.00 on top so the customer will pay £120.00. When you pay a supplier, you will be charged input VAT (B) at 20% assuming the good or service sold to you is standard rated for VAT.
At the end of your VAT quarter, you will complete and submit a VAT return. If your output VAT (A) is a larger figure than your input VAT (B), you will pay the difference to HMRC. If your input VAT is a larger figure than your output VAT (B), you will receive a VAT refund. In net terms, you pay no VAT as A is offset against B.
I hope this heps but let me know if you have any furtehr questions.
What type of business are you in?
Any exepnses you incur in connection with the business should be allowable expenses which are offset against your business income. If you are not VAT registered, you would claim the VAT inclusive expense, let's say £120.00. If you are VAT registered, you would claim the net of VAT expense, £100.00, as you will effectively be recaliming the £20.00 VAT.
Wages dont' have VAT added.
You are confusing two different animals, expenses and VAT. VAT is charged on the value of the service a business provides and on expenses it pays. Those VAT charges are netted off against one another. The net expense is claimed against your income in your accounts.
You ought to have an accountant look at the business you intend to operatae in detail. If you don't pay much VAT on your purchases, then it probably won't be worth regsitering for VAT voluntarily until you have to register based on your turnover as you might have to charge VAT on the fees you charge which would affect your competitiveness.