Build me a sms sender with good ui and ux with online server and software to users

I need a sms sender that’s is good and user friendly That I can add my api key from android sender to it And once user and sms it will auto send from my sims connected to android phone / if you can choose to build me completely a script to connect to the sims via pc and users can buy sms from me credits and it send form sims connected to my sim pool and once their credit exhaust they can buy in that software that I send them