While I require this process to be verified, I have used Google's instructions here combined with my intuitions to solve this issue.
Login into squarespace.com and go to account.squarespace.com.
Then, click on the "Domains" tab on the top left of the dashboard.
Then, click on the domain you are having an issue with.
On the left dashboard, click the "Websites" section.
Afterwards, scroll down to the "Domain Forwarding" section.
Select the black "Add Rule" button on the left of the "Domain Forwarding" title.
In the "Forward from" input, put in a single "@" and in the "Forward to" input, put in your domain with a "www" in front.
Afterward, I saw changes happen within 10 minutes.
If this Forward step gives you errors, retry after setting up the DNS as seen here. The DNS must be set up using this protocol as dictated by Squarespace, the Squarespace defaults don't seem to work.
In addition, I do have the "www" prefix toggle off per Squarespace's instructions, but it did not work properly before I used redirect as seen above.
Hopefully, this works for all of you as well — best wishes, especially to "noobs" like me who are trying to make their portfolios.
Edit: forwarding suddenly stopped working for me, I had a strange solution. Using information from Squarespace forums I had gotten prior, I went to the "Custom records" sections and input information from one of the rows in "Squarespace Domain Forwarding." After that it seemed to work for some reason. It may have had something to do with SSL certificates, but in general Squarespace's domain forwarding seems a bit buggy.