I you are just 'finishing' your license then maybe you haven't done your exams yet? Have a look at Air Law which covers both of your questions. Frankly your questions and the phraseology you use leads one to believe you are not very far along on your PPL. Good luck anyway.
Why can people not just plainly answer questions instead of arbitrarily criticizing them and the person asking?
That just DISCOURAGES folks to ask more questions because they think their questions might be regarded as "stupid".
So here we go.
1. Don't you need to be in sight of the ground for VFR? Can you do that if there is fog over your flight path / below you - or can you see around to ground level?
Depends on country regulations, licenses, and airspace. For the EASA PPL in uncontrolled airspace, there is no "surface in sight" requirement for VFR flight.
2. If the fields you are flying over are IFR only would that not disbar them as possible alternatives in case of the need to put down - so choosing a different route might enhance your safety overall?
True but that's at your own discretion. The same could be said for overflying mountaineous terrain (possibly at night!). It's obviously riskier than flying over flat, rural areas with dozens of suitable landing fields in gliding distance, but it's not illegal.
Some pilots will bet their lives on the collection of nuts, bolts, castings, bearings, pipes, mags etc that comprise a running aero engine. I'm not one of them, and it's why a not insignificant part of the PPL syllabus is dedicated to forced landings without power.
But then again, we all know that the higher risk factor is the collection of water, proteins, fats, gases and such that comprise a living human body and mind. I'm one of them, and it's why an entire book and exam in the PPL syllabus are dedicated to human factors.
