Suppose: Gallery Images on page A, corresponding sections on page B
To achieve this in Squarespace, you can follow these.
#1. First, edit page B.
Hover on each section > Click Edit Section
Scroll down and enter #suites01
Similar with second section: #suites02
Third section, #suites03
#2. Find Page URL of page B.
In my example, it is: /services-all
#3. Edit page A > Edit Gallery Images > Enter these URLs.
/services-all#suites01
/services-all#suites02
/services-all#suites03
