Due for service...pls help

[InnerDevil]

Just about about to service my car for the first since buying it 3 weeks ago
Gettin my mate whos a mechanic to do it, but i told him ill buy the (performance) oils & parts tho.....but im unsure of wat to buy

Firstly the kms are 113, 000

Been looking on the forum for the motor oil u guys use and have decided in either castrol edge 5w-30 or penrite semi syn (unsure wat viscosity tho?)

Also wanting to replace the fuel filter but unsure wat type or size fits or is the best?

And last but not least, wat radiator coolant to use
(: i know this is a stupid question...but wheres the radiator cap? lol)

And is there anything else to change or replace ?
(considered iridium spark plugs but are abit pricey.....so savin for those)

Thanks
Pete