Building a credit history (with cc?)

DCP11C

I will be a student come September and I want to build up a credit history because I now understand how important it is. One of my initial ideas was to obtain a credit card and honour the debt by paying it off within the time period.

I have been doing some research and one possibility of a credit card is one from Vanquis, however reading the Terms and Conditions I was concerned by the wording (under 3.7)

***In respect of Purchase Transactions on your first statement, you will be charged interest from the transaction date until the end of the first statement period but, if you pay off your first statement balance in full, you could get up to 28 days interest free credit.***

=Does this mean that if I pay of debts within 28 days I will get "interest free" credit?
So basically if I bought something at £10 I would pay back £10?

=Also I have no job at the moment (income from interest and student loans) but I have savings to backup the credit, if that makes sense. So will I be considered to get this credit card?

Thanks for any help.