No, but you can say informally: I sure am happy

--, It is an interesting question. DO + BE You can use 'do' as an auxiliary with “be” to emphasize the imperative. -Do be sure! -Do be happy! You can use "do" for emphasis with other linking verbs. -I do seem sure. -I do appear to be happy, don’t I? But the emphatic 'do' is not normally used before the verb "to be" in standard modern English. -I do be happy....not acceptable -I do be sure......not acceptable However, you could ask yourself a rhetorical question, -Why don't I be sure first, before I act? It is also possible to use do + be in the subjunctive. -The boss insisted that I do be careful. In some dialects, Irish English, Caribbean English, and American Black English “do” is used before “be” with a special meaning. -I do be happy.....meaning.....I am usually happy. -I do be going to McDonalds........meaning ....I regularly go to McDonalds.

You can say using the imperative : Be sure Be happy However you can't say : " I do be sure /happy." Here you would be using 2 auxiliary verbs ( be ,do) consecutively and this is a grammatical mistake.