What Video Camera and Tool is best to Produce Interviews & Small Docus for my Contruction Company?
This question is really super broad, possibly too much so, however I will try to offer some general tips for starting out in video.

The most important thing with video is having a stable shot.  Whatever you do, you will want to use a tripod when shooting.  If you don't have a stable shot, then no amount of equipment, editing or content is going to make up for it.

Next, you need good lighting.  If you don't have proper lighting, you can't have good composition.  To read up more on lighting, I suggest looking for basic information on three point lighting.  It isn't a panacea, but it's a good starting point from which to build.

Next, you need to make sure the shots are well composed.  This is a bit of an artistic call and while concepts like the rule of thirds can be helpful guidelines, really, look at what other videos do and try to match the way they pose and position subjects within the frame.

Finally, of pretty much least significance is the gear itself.  In a pinch you can use a smartphone camera for shooting video.  It has been done and a skilled editor can make use of such footage.  

Moving a step up from that, you have low cost, limited functionality but high quality cameras like the GoPro which can capture great video, but are very limited in their range of functionality.  Camcorders can also work if you need a little more functionality at a slight cost in image quality.

Another step up from that, if budget allows, is to move in to DSLR cameras to use for video.  It's important to be aware that many DSLR options do not support auto-focus while shooting, though some newer ones do offer auto-focus during video.  DSLRs have the major advantage of larger sensors than camcorders and smartphones.  This means that they can get a much nicer depth of field and allow for background blur to be achieved much more easily.

Editing is an even more complex beast.  There is a wide range of editing software options available and the ones that do the best jobs are generally not the easiest to learn.  Additionally, editing is more than just understanding the software, it involves understanding the language of video and how video is used to communicate ideas.

This question already addresses video editing software from a beginner's perspective, so rather than elaborate here, I'd suggest checking the existing question that already covers that portion of your question.