I need an excel file to calculate the employees annual leave

What I need is an excel file that calculate an annual leave for employees knowing that an employee can get 21 days per year ( meaning 1.75 each month ) , until they complete the 3rd year when they start the 4th year he can get 30 days per year ( meaning 2.5 each month) Also for those who are less than 4 years can’t accumulate more than 42 Days ( meaning if an employee didn’t take his annual vacation for the first year ” 21 days ” he can save it to the next year but not the third year) same rule for employees who are working for 4 years and more.

I’m uploading the file i’m working on feel free to change what it’s needed