Hello. I have created email programs which read emails, so I am familiar with what you need.
So the program will be a desktop app, with a timer for checking your emails. Of course you can change this any time. It will login to your gmail account -you will need to give access to external apps- download the emails and do the scrap. Then it will place the data to the excel. There will be a settings file, so you can alter the checking interval, login user and pass, file names, folders etc. I suggest using a database for saving which is better, but excel is ok also.
Regarding your future projects, since the basic part is reading your emails, I can add extra code for other types of emails so you can have it all organized with one program.
Please feel free to ask any questions.
Regards,
Marina Louki