Functional spreadsheet that can be user managed after creation

I work in sales, for an insurance company, we have a functional mobile app that allows us to send copies of a group letter to affiliated individuals informing them that their benefits through the group that they're affiliated with are ready to be delivered. We have a company accessible digital platform which I'm looking to utilize without any of the source material, ie copy and paste data from my company website, none of which has encrypted are protected nor need it be, primarily basic customer information, provided by the customer to use it, more or less for a marketing campaign wherein I can eliminate people who've been contacted by matching the start data to missing data in future versions. So basically I want to be able to remove individuals that have been contacted whose service has been completed from the master list, by a spreadsheet that has a search function that then returns the cells with the missing values and displays another spreadsheet with only the remaining individuals who have yet to be contacted. This needs to be reloadable on a monthly basis by the user (me). So that a whole new batch of customers can be systematically eliminated through their service period. The construction of the initial spreadsheet can't be that difficult because I have a rough idea of how to do it myself and I have very little computer science experience. But I want to use it in cooperation with a 3rd party website for text marketing to this client base. The client base will rarely if ever exceed 1000 individuals. The only information I need to store on them is their name, their phone number, and the group thru which they are affiliated. Ideally their hometown or zip code would be another category. overall I'm trying to increase efficiency for my sales team to prevent them from having to individually message these people, by using the group texting website to contact every member of a specific affiliation simultaneously to alert them when were servicing the area. Hope this is the correct amount of information to provide.