I like Gustavo's use of "and so is Hamza" and, like him, prefer the second example to the first. I'd just like to note that the first sentence, though awkward, is not incorrect. The awkwardness owes to the "to, too" combination, and that can be overcome by changing "too" to "as well":
(1a) Muhammad is going to learn English, and Hamza is going to, as well.