Hey mate. If you don’t have the know how, tools, or know someone who does, I’d probably recommend taking the PS4 to a repairer. Here in Australia, our equivalent of GameStop will repair PS4s for about $150AUD. If my father wasn’t an electrician who built arcade machines for a hobby I’d be doing exactly that.
Might be worth telling the repairer that you think you know what the issue is but can’t fix it yourself. Might save you being dicked around.