Autofilling or creating a dropdown menu for a monthly shift schedule

Hello guys and galls,
First and foremost I would like to thank you for your time.
The situation is this:
My wife is taking a long time (more than 10hrs per month) to plan a work schedule each month.
Now, it ain't easy what I'm about to ask you and I know this because I am a more than basic Excel user myself.
With no further ado I attached the current sheet she is manually working on.
Monday to Friday there are 3 shifts that need to be color coded (blue the morning shift, green dayshift, and red the nightshift). On the weekend there are 2 shifts only but have a special rule that says no less than 24h between the shift of a worker.
Each shift has 2 different type of workers and each shift will have both types of worker.
There are also the vacation days that need to be filled.
Is there a way to automate the process if enough amount of data has been preset?
I'm thinking about this solution: There is a shift for each individual worker that my wife fills at the start of the year with the vacation days. so we got that figured out.
This month shift sheet needs to remember last day from the previous month shifts in order to autocomplete the shifts.
In order to be correct it should know that any worker can't have more than X amount of working hours per month.
Please notice that there's a line between worker 12 and 13 i drew it to separate the 2 types of workers.
I am pretty certain that an automation would be difficult to implement but what about some dropdown menu or some sort of help in order to calculate/draw the schedule in much lesser time?
Anyway thanks again

Welcome to the forum.

Office 2018 does not exist, please correct it for us to give you the best solution for your Excel version.

Your sheet does not provide much information to do things that you request, like there is no time.

Moving on, I prepared your calendar to react to the change of each month and year, also weekend. Feel free to play with it.

Thanks for the welcome,
You're right I updated with the correct information right now.

Originally Posted by DJunqueira

Your sheet does not provide much information to do things that you request, like there is no time.

Moving on, I prepared your calendar to react to the change of each month and year, also weekend. Feel free to play with it.

Well you are right, it doesn't provide the information since it was being done by hand.
I had to anonymize the sheet so i took some of the info out.
But basically there are 2 employees in the upper tier and 1 in the lower that are assigned for each tier.
I'll update with a small sample filling the required information in.
I updated it. So please feel free to ask if there are some things I haven't explained them right.
Thank you

Hello,
Thanks for the time you spent helping.
Although I'm pretty far away for the desired goal, your help is indeed a push in the right direction.
I need for instance some more stuff to be inserted/ to be accounted in the schedule. For instance vacation days, sick leave etc. I get it now, it's through conditional formatting. Although i'm not very familiar with it, i'll be playing a bit with it.
Another thing I want is to automatic generate the next months schedule by remembering the work states of each employee. But also to automatically create the frame (start of the month and weekends). Idk if i'm making myself very clear with this.
Another thing i want to do is: to have a cell or a column in which I can set the maximum amount of working time an employee can have. Or maybe even better a counter (like a sum) that can remember if an employee has vacation days or has some free days from the previous month, for instance.
I know it's a lot of rules and stuff but as I stated in the first post, this schedule eats a lot of time from my wife's life and I want to help her as much as I can by automatizing it or by any other means.

Yeah thank you.
It is somewhat better but the other issues with autoselecting the starting day of the week and more automation are more difficult I guess to implement. I tried using the excel ai bot but i think the task is too complex for it.

It's a small issue no problem with that. The automation of filling the schedule is the hard part

Thank you for your patience and your time, now we're getting closer.