A boat that's been recently repainted is unlikely to have been neglected badly in other areas.. I'd stop worrying and concentrate on learning the ropes before trying to replace them. Even badly aged lines rarely 'break' unless they are visibly damaged - they get stiff and may not run freely though blocks etc. - but even then you can throw them into a pillowcase and put them in the wash - you may be amazed at the rejuvenation that can produce.
Having a sailmaker inspect things will provide peace of mind that may well be worth it.
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
1984 Fast/Nicholson 345 "FastForward"