How freely can I travel with the advance parole document?

Advance Parole (AP) lets you travel, but it never gives a 100% guarantee of entry.
That said, for someone in your situation—Indian-born Canadian citizen, EB-5, clean record, no status violations—the risk after short, ordinary trips is generally low. AP allows you to request parole into the U.S., not “admission” and is dependent on your AOS remaining pending at the time and not denied.
If the AOS has been denied, you will be refused admission. CBP always has discretion at the Port of Entry and will review your record to ensure your AOS is still pending and that there are no other factors that could render you ineligible for parole back in to the United States. This is true for everyone, including green card holders—but the standard for denying parole when you have a valid AP and no issues is high.
For short trips (days or a few weeks), your parole back to the US is very likely, assuming your AP is still valid, as stated above, your AOS remains pending or is otherwise approved, and you have no criminal issues, immigration fraud, or misrepresentation and finally, no prior overstays or unauthorized employment that wasn’t already disclosed. However, it isn’t legally “assured”, but for clean cases it’s close in practical terms.

For long or frequent trips, extended time abroad or repeated long absences can raise questions about whether you’re abandoning your adjustment of status. Unfortunately, there’s no hard rule like “X days is too long,” but months abroad start to get uncomfortable unless well-justified.
Important things to watch out for:
* You must reenter using AP only unless you have a valid H-1B/H-4 or L-1/L2 visa – there are on the only 2 visas that you can travel and return under without abandoning your AOS. Present your AP (or combo EAD/AP card) to CBP.
* If your I-485 is denied while you’re abroad your AP becomes invalid immediately and obviously you would end up being stuck outside the U.S. While it may be possible to file a MTR to reopen your denied AOS, the personal consequences to you could be dramatic. This is rare in the context of an AOS based on an EB-5 filing unless there’s a project or source-of-funds issue, but it’s the biggest theoretical risk
* Secondary Inspection is common – the first line CBP officers will not be in the position to do a complete database search for your case, so practically speaking, if you have a connecting flight AFTER you are to be inspected at the Port of Entry, make sure that there’s sufficient time between both for you to be inspected and paroled – I’d recommend at least 3 hours to be safe.
* AP validity & multiple entries - check whether your AP is multiple-entry (most are) and obviously do not travel if it expires while you’re abroad
* Documentation
* AP document – must be valid for date you plan to return to the US
* Passport – same, must be valid for the date you plan to return to the US
* I-485 receipt notice
* EB-5 filing receipts (I-526E / I-526 if applicable)

If you have an H-1B visa or L-1A visa, you can travel while the adjustment of status is pending. If you have a valid advance parole you can travel with the adjustment pending. Advance parole means you can return to the status you had when you left and, absent any major changes, you should be able to travel abroad for short trips and renter but you will be sent to secondary inspection so expect delays.