Modeling is an extremely competitive business. You need to realize there are many qualities a model needs to have. Mostly, you need to be healthy. You need to have clear skin, a full head of hair, and very good symmetrical features. You may want to work with a fitness trainer and talk to them about how you want to look and your goals to become a model.
Decide what kind of model you want to be. Technically, anyone can be a model. But if you do not reach certain requirements, you will not make it very far. If you have a curvy body, you may be able to make it as a plus size model. But, they also look at facial features as well. For a catwalk model, you will need to be very tall. Usually you will at least need to be 5’7 or 5’8. You will also need to be very skinny with a small breast size.
Underwear models can very, but usually you need to have a large breast size and small hips. There are other types of modeling you can do if you do not fit the face or body qualifications. You can be a foot, hair, or hand model for example.
Know what kind of look you want to go for. Also know what you can pull off. If you want to be a lingerie model, you need to be very skinny, but with a larger breast size. You may be able to pull off more than one look, so keep working on it.
You will want to get some photos done. They do not have to be professional, but they should look like you have the ability to be a model. Most of the time, you will need at least one head shot and one full body shot. However, you will probably want to get some professional photos done.
Look up some local modeling agencies and contact them. Always be professional and polite and be prepared to take criticism.