How to send text messages to invite national defense experts?

The contents are as follows: Dear xxx, our company will hold a seminar on xx on X, X, and you are cordially invited to attend. Your presence will be our honor.

Brief Introduction of Short Message Service (SMS): It is a part of Unified Communications business plan. Users can directly send or receive text or digital information through mobile phones or other telecommunication terminals. The number of characters that users can receive and send short messages at a time is 160 English, numeric characters or 70 Chinese characters. Short message is a telecommunication service in digital mobile communication system. It is a non-real-time and non-voice data communication service to transmit text or digital short messages through the signaling channel and signaling network of mobile communication system.