Yes, But there is one general condition.
If the courses you have opted for fall in the same group, then by all means, go ahead and state your choices in one single application form.
However, if you opt for courses in different groups, then you will need to fill out separate applications.

You can but you have to apply separately for both and pay the fees separately. For B.Tech the fees will include the MU OET test fees also. so the charges may be higher ie The B.Arch application will be 600 and the B.Tech will be 2000.