In a japanese anime I've heard lots of "de gozaru" in a casual speech. If I use it with my friends, will it sound ok?
You're talking about Prison School, aren't you? Gakuto is a comic relief "weirdo" character. He doesn't talk like modern Japanese. A lot of things he says is weird/uncommon these days, like 小生 and 皆の衆. (But if you're not talking about PS, then sorry, but it still stands that it'd be extremely weird to say でござる; imagine a friend of yours just starts saying stuff like ye, thou, thy, generally imitating a Shakespeare character).