I found it easy to start 3D modelling on iPad after reading this tutorial
Briefly

In the field of 3D design, polygon modelling and sculpting stand as two essential techniques, each tailored for distinct needs. Polygon modelling involves creating models by manipulating individual polygons and vertices, ideal for technical and structured designs. It's optimal for scenarios that necessitate precision, such as mechanical models. In contrast, 3D sculpting resembles clay modeling and is preferred for its fluid creativity in shaping organic forms. With recent advancements, including mobile applications like Valence 3D, the access to powerful 3D modeling tools has expanded, enabling artists to work flexibly across devices.
Polygon modelling is ideal for creating structured and optimized models, making it crucial for real-time applications like video games and interactive media.
3D sculpting resembles working with clay, favored for its intuitive shaping of complex, organic models, allowing for creative and artistic freedom.
Read at Creative Bloq
[
|
]