In reality,anyone can potentially become a model, as there are limitless categories of model styles and requirements,from staightforward catwalk to adult fetish work.
The truth is of course that the more unconventional type of model is going to have less opportunities for work than a glamour,topless /page 3 style model.
With regard to glamour and topless work, you should not be put off if you have large or small breasts
or are tall or small in height , or indeed over a size 12 dress figure.
In addition,you do not have to be conventionally pretty, but again you do have to be realistic about work opportunities