Here is the document on how to Mute and Hide a contact.  You cant block someone in teams for work.  This will mute notifications and calls and you wont see them.

https://isihq-my.sharepoint.com/:w:/g/personal/jammy_fitch_biz-solve_com/EQ-ZYiSnLMlMn2dawqrCe64B6E4S2T2WHO6KXTBiag84XQ?e=8u3iov