What is the difference between character_set_client and character_set_connection?

Question

MySQL

Question 1 : Let's say character_set_client = cp1251. Does this mean that the MySQL server will expect cp1251-encoded sql-query text from the client?
Question 2 : Now, let character_set_connection = utf8mb3 and let it be required in the sql query to compare the string with the type field of the animals table. The type field of the animals table is encoded koi8r. The query, for example, is:
SELECT id FROM animals WHERE type = 'cat'.
MySQL server receives this request in cp1251 encoding, then converts the type record field from koi8r encoding to utf8mb3 encoding and the string 'cat' from cp1251 encoding to utf8mb3 encoding, and only after that does it compare (according to the set collation)?
Question 3 : In the ODBC driver, the connection string says

The line "STMT=SET CHARACTER SET cp1251;" sets the client encoding (character_set_client)? And if it is missing, then the default value set by character_set_client = cp1251 in my.ini will apply?
Am I understanding everything correctly?