Custom Post Types are a great feature in WordPress for having entries that do not fall in the standard Posts and Pages buckets. Ex.:
The most popular method for registering a Custom Post Type (CPT) is using the Custom Post Type UI plugin.
To add a Custom Post Type, install and activate the above plugin. Then go to CPT UI > Add/Edit Post Types.
Fill in the slug, plural label and singular label fields.
Scroll down to the Settings section and change Has Archive to True.
This will enable the archive (listing) page where all your CPT entries can be seen.
By default, this will be present at https://yoursite.com/<cptslug>. Ex.: https://yoursite.com/project. You may want to enter the plural term here so that the archive page URL will be https://yoursite.com/projects (for example).
Scroll down and click Add Post Type.