Google sheet expert

I am the manager of a training department of a BPO. I am looking to automatize the way that my trainers report the attendance of each group we are training. Not only this but also that I can add a new group, amount of days of 3 training stages, amount of headcount, holidays off (Based on colombian law) and that will show me a general view of where each team is day by day. I have this but I do it manually and would like to automatize it with a Macro or related. My trainers will need to have access to the file as viewers so they see where they need to be each day. Also, that from 1 general page I can go to the view of general attendance and headcount, each wave calendar and all possible details as I have 10 files that I fill out manually every day. I would like my trainers to update their attendance on a daily basis and that my main file is automatically updated. Used to have this through excel in other company but do not know how to use it in google sheets.