Do they regard the whole claims to reject a patent based on Prior Art or only independent claims?

Question

Let's bring an example (note I am naive in writing or understanding claims):

Independent claim 1: It is an awesome equipment to detect X,

dependent claim 2: the equipment of claim 1 detects X using a fork.

Could they reject it because an equipment to detect X already exists (no matter if they use spoon in their dependent claims)?

For example if I write it as:

Independent claim 1: It is an awesome equipment to detect X using a fork

Then could it be accepted because there is "fork" in independent claim while the independent claim of the others was general?!

Answer 1

Could they reject it because an equipment to detect X already exists (no matter if they use spoon in their dependent claims)?

Yes, Claim 1 will be rejected if the examiner finds prior art showing that equipment to detect X already exists (and you have a duty to bring such prior art to the examiner's attention if you know of it).

Dependent Claim 2 will not necessarily be rejected. However, if you cannot overcome the rejection of Claim 1, the patent cannot issue as written. It will be necessary at that time to amend the claims and import the limitations of Claim 2 into Claim 1. Amending claims in this way is always permitted and should never give rise to a new matter rejection. However, patent applicants will usually look for ways to add additional limitations to their independent claim that don't narrow all the way to their dependent claims but still patentably distinguish over the prior art. Of course, this is a lot trickier because of the possible new matter issues.