Google Sheets Formula - Function

We run Apartment short term rentals. We use google Sheets to enter specific Data of every reservation, check pic 1. I want a Formula or script Function which searches the dates of the reservation, the platform the reservation made and the number of guests, and put the result in the other calendar in the same sheet (if possible to merge the cells of the same reservation). Also I want a suggestion to resolve problem on the appearance of double bookings, if any.

2nd thing I want is to use the conditional formatting under the Key column in the first pic AB and AC columns to check if 3 conditions match to turn into purple the cell:
First condition is the cell in the same raw with V column to be purple like in the picture.

3rd also conditional formatting formula when we put a number in Column V in pic 1 to change the color to purple of the cell in the raw of column V in pic 1 if it checks in pic 3 in column U if is Y and the number in column A in pic 3.

4th I want if possible to read the phone number and send a specific message (Specific days before arrival) through whats app or sms

5th in pic 2 the column D to check pic 3 in column S to bring the result of the room's capacity and after a conditional formatting to change the color of the back in pic 2 column D, according to the number of bathrooms in pic 3 column O. We'll inform you for the specific colors.

6th We want the Bookings sheet to have the ability of issuing pdf invoices and receipts because has all the details needed. For the accommodation and and extra invoice for Transfer, service or product for the guest.
Also we want to communicate with the warehouse to control stock. (The Pdfs of receipts will be stored in file folders automatically by month)

7th We want a new sheet to have the ability to have access to inventory and issue pdf invoice and receipt multiple products, transfers or services invoice and control the warehouse. (The Pdfs of receipts will be stored in file folders automatically by month)

6+7 th Both will store invoice and receipt list in a single new sheet for easy access and data migration.

8th Security of the sheet We want the ability to give access to specific sheets for a user and do not have ability to see or also modify all sheets, if possible.

9th We'll have full access and licence off everything will be done.

10th conditional formating with formula according 2 factors.

11th we want in the first Sheet with the calendar with the name KRAT when we press to see the Sheet or open the document to see by default the current day (-2) and after we can go front or back.