You can go without a guide, but I wouldn’t recommend it on your first time.
When I went up I had two friends going up later behind our group. One of them had done it several times the other was on his first attempt but was in excellent shape. So they went across the belly crawl and instead of heading up the chimney they went a little further to the north. They ended up in a real jam but summitted anyway. It made for some hairy stories that we can laugh about now, almost 20 years later.