OK, so it is very easy to get bogged down in a giant monster of interlinked stuff, and not get anywhere with any of it because you're forever going around in circles.
If you aren't overly proficient in Excel then it isn't the end of the world, as these days there is so much information on the internet - you're no longer reliant on the often sparse information from Excel's own help menu, although that is better than it once was.
Approaches to this type of task perhaps vary according to the different ways our brains see problems, interpret patterns, and manage data, so there isn't necessarily a definitive "right" way to do it. Just keep in mind that your colleagues may see things in other ways, and sometimes this can be very helpful!
I'd be inclined to start by creating one document. Get the basic headings for the parameters you want to record, and the basic layout. Don't worry about making it too pretty at this stage, as you'll almost always realise you've forgotten something and need to rejig all your work to add it in part-way though 
The fewer interlinked documents you have, the easier it will be to manage, so whilst it's tempting to go down this route (and it's quite satisfying seeing all the data move around the sheets, if/when you've finally got it working ), I'd try to see how much you can get into a single sheet. It might end being very wide, with lots of columns on the main page, but a single record with batch number, product type, start time, end time, man hours etc might well be feasible to allow all of this to be entered into one place, making it more likely to be completed routinely. Just start putting column headings for what you need to record. This might be all you end up needing, or it might end up as your master data entry point, and the numbers may then be pulled across by other sheets or workbooks to do their own thing.
Getting that data out and into a useful form is then your next challenge, so you want to have a thing about what you / your business needs to know. Perhaps a second sheet within the same document could give a useful summary page - e.g. a table with a line for each month, showing number of batches produced, total kg produced, total man hours worked, average hours per 1000kg (or whatever is relevant to you) etc. Similarly you can generate graphs to show you what is relevant to you.
If you're pretty new to Excel it might be worth doing an introductory course?
There is loads of information on the internet these days, so learning to use new formulae is far easier than it used to be, but getting the most out of this type of resource will be easier if you know how to ask a search engine exactly what you're looking for.
