かける（かける）— make a phone call
ココさん が 電話 を かける と 思います。
I think Coco will make a phone call.
かけるかける
make a phone call
かける
accent [2]In detail
Words
ココさんKoko-sanCoco
がga(subject marker)
電話denwaphone call
をo(object marker)
かけるkakerumake (a phone call)
とto(marks the content of a thought)
思いますomouthink (polite)
ますmasuthe polite ending in 思います
電話をかける means making a phone call. Learn it as an expression; かける has many other meanings. 電話を切る means ending the call.
Coco-sensei