Should your first horse be a stallion. No. Beginners should not consider buying a stallion as a first horse. Why? Because no matter how old, well trained or placid tempered a stallion is, his first priority is breeding mares. This means he may never entirely be giving you his full attention and that attention can quickly be distracted by a mare. That could place you in a difficult, and possibly dangerous situation.
Stallions have been known to go over, under or through almost anything to get at a mare. Even while being ridden or driven, a stallion can ignore his handler, and even become dangerous towards them. An experienced horseman may know how to deal with this situation and avert any undesirable behavior. But as a novice horse owner you may not have the experience to manage a stallion.
It may sound prestigious, romantic and exciting to own and ride a stallion. But stallions should only be kept because they have outstanding traits of conformation, temperament, bloodlines and performance records that make them worth breeding to. There are of course, exceptions to every rule, and you may know of a wonderful stallion, that has made a wonderful first horse for someone. But these are very, very rare, and for beginners, a mare or gelding would be a safer choice.
Likewise, it’s not a great idea for new owners to leave their colts un-gelded. In Should You Keep Your Colt as a Stallion? I discuss why it’s probably a good idea to geld that young male horse you raised or just bought.