Wow, that was quite a lot. I must admit that I have never considered how many types of fields Salesforce offers. If you were to ask me whether you must memorize all of this, I would say it is worth it, but you will get used to it as you start working regularly with Salesforce, as creating new fields is one of the many tasks you will perform or are already performing as an administrator.
Once you choose the type of field, give it a name, and assign the appropriate values, you must decide whom you want to grant access to. You will see a group of all profiles and can choose for whom this field will be visible and for whom it will be read-only. The next step is to add the field to the appropriate page layout. And here, we have two options: to add or not to add, yes, I know, surprising. If you add the field, it will appear in the first section of the page layout, but possibly not where you would like. If not, open the page layout and find your new field, which you can place anywhere.
Another essential feature is default values. Almost every type of field can be assigned a default value. Every time you create a record, such a value will be entered for the newly created record. For instance, let us say you run a podcast on Spotify, and you collect listener data in the system. You have a premium program where, once a listener listens to at least 50% of the material from your channel, you send them a shirt. By default, a Contact is not a Super Fan, so the default value is just Fan. So, when creating a new contact, the Title field has the value Fan. But when all the conditions are met, the field is overwritten with the new value Super Fan.
Access can practically be granted or revoked to any element in the system, and the same goes for fields. We can also assign specific properties to fields. We have two such options: Read-only and Required. Read-only is assigned to fields that cannot be edited. The value might be overwritten during creation, integration, or automation. Required is an option for those who forget things. How often did you check something in the system and lack a phone number or email address? That is where the required option comes in handy. Thanks to this feature, the system will enforce the entry of a value in the field required.