Maybe you can use this website：https://app.biorender.com/

This simple Web application helps you chart the fields of biotechnology, immunology, neuroscience and more life science research.

I received these links from colleagues but have not used these tools myself.

Hope it helps.

1)__ CCBuilder 2.0: for coiled-coil modeling

A web-based application that can model structures for a whole class of proteins,

https://onlinelibrary.wiley.com/doi/full/10.1002/pro.3279

2)__ Rosetta and the user group, "Rosetta Commons"

A suite of molecular modeling and search tools called Rosetta. Can calculate the energy of a folded protein and search for the lowest energy sequence for a given structure, or the lowest energy structure for a given sequence. Developed by Baker Labs in the late 1990s as a tool for predicting structure. The software has been under continuous development ever since, both by members of his lab and a community of several hundred users called the Rosetta Commons, to improve its performance and capabilities

3)__ the MNNN model for prediction of protein structures.

see this link

https://www.biorxiv.org/content/10.1101/660639v2.full.pdf

4)__ COOT and Phenix to model structures

see this link for download

https://phenix-online.org/download/other.html

and this for user documentation

http://www.phenix-online.org/documentation/coot.html

5)__ Phaser Crystallographic Software at this link https://www.phaser.cimr.cam.ac.uk/index.php/Phaser_Crystallographic_Software