HELP NEEDED: Force a URL

Does anyone know if it's possible to force a specific url onto a single page in squarespace without using a dev site, javascript, or hiring someone to do it? If so, what is this called so I can find more information?
SQSP doesn't allow for the slug characters needed. Have a strange situation where a web page needs to match an old address exactly. Redirect doesn't work for this.

Note: I was told by Squarespace support that this was possible. They gave me a link to the main forum page and a link to the Custom Code FAQ and refused to give me further information. 

I assume  the domain name, not the slug name, is still the same as the old address?

8 hours ago, derricksrandomviews said:

I assume  the domain name, not the slug name, is still the same as the old address?

It is, the domain has been forwarded from GoDaddy (if that's any help at all). However the old site was http. The old page address I'm looking at is formated like this: http://www.businessname.com/SOFTWARE_Current.html  

The address has spaces  after the word software?

Underscore. Guess it isn't visible with the formatting on here.

Hi, was there resolution on this subject? I have the same issue; rebuilding a site in Squarespace but my old URLs all have underscores. Was hoping to just choose the same slug for each page I'm rebuilding, how do I get around this?

https://www.soufrafilm.com/the_people

Thank you!

6 hours ago, lisamadison said:

my old URLs all have underscores. Was hoping to just choose the same slug for each page I'm rebuilding, how do I get around this?

On Squarespace, URL slugs can't include special characters other than dashes (-). To get around this, use dashes instead of underscores and then set up a redirect for each page. For more information, see URL redirects.

For example, 

/the_people -> /the-people 301