I am new to Odoo, can you tell me where to write these codes? Can I do this easily?

Hi,

Please try like below.

_inherit = ["image.mixin"]
_order = "sequence, id"

name = fields.Char("Name", required=True)
sequence = fields.Integer(default=10, index=True)
image_1920 = fields.Image(required=True)
related_document_id = fields.Many2one("your model", "Template", index=True, ondelete="cascade", invisible=True)
can_image_1024_be_zoomed = fields.Boolean(compute="_compute_can_image_1024_be_zoomed", store=True)

For getting the preview.

https://ibb.co/kxSrxqH

Regards