There is an Amharic alphabetical letter missing in the earlier translation ("አስቀም"). It should be "አስቀምጥ". Regardless, the earlier translation does not fully capture the exact action of what we are trying to do because "አስቀምጥ" roughly translates to "put". Therefore, it doesn't fully capture what we are trying to perform. Whereas, "ሙላ" does capture what we are trying to do. In addition, "ሙላ" is also the word we use when we ask someone to set a date or alarm for us.
It should be said that if we are dealing with the word "Set" with respect to choosing an item from a list of options available (like the list of colors available above in the screenshot) the best way to translate it would be to use the Amharic word "ምረጥ". i.e "Set" for time-related settings "ሙላ" and "Set" for list-related settings "ምረጥ".

Even though the word "አስቀምጥ" doesn't fully capture the essence of "SET" in this context, it is as close as it could get to the word "SET" in this case, "ወስን" can also be used as an alternative but "አስቀምጥ" is a much better choice in the current context.