Use the text below as a starting point and customize to suit you needs.
Dear [boss],
As you know, I spend a good part of my day in Excel.
Although I can usually figure things out, I could be more productive with training. I think this might be a good option:
The training is self-paced, with short videos I can fit into my schedule easily.
The site is well organized, and they get good feedback.
Would the company cover the cost as part of my skills development?
Please let me know what you think.
Thanks,
[your name]