The reason why i couldn’t find UiPath.ScreenOCR.Activities was because Official was not checked, and I followed these steps to find it.
In Studio, click Home; Setting, and then Manage Sources, then check official: refer to the screenshots below:
and then refer to this link below if you need The APi Key: UiPath Screen OCR: Now in Public Preview! - #12 by pradeepRPA
Anil_G
ashokkarale
furkan.cosan
Anelisa_Bolosha1
edevries
Nitesh
pikorpa
dheephiga.am
SUDARSHAN_SHARMA