engines gonna die? Options

[DeathWing]

ive been hearing a knock knock sound on the 3000-5000 rpm inside the engine...a newbie mechanic told me tha should be the engine parts inside tnat are gone (i always try to drive at the lowest rpm i can)

i initially heard the sound when i bought the car without giving it enough importance, always keeping the oil full

so it must be that the engine will be gone soon, that means the car should be gone too, im very sad