Upvote:-3
If you play the video game Batman: Arkham Knight, it actually borrows the same concept: The suit is armor worn underneath a to hold the armor plates.
Real knights used similar systems, knights wore a long tunic shirt called a aketon or gambeson which had attachment points to tie one's armor on.
Men's gambeson, c. 1660–1670. Collection Centraal Museum, Utrecht.
Upvote:5
If you want to have a look at how individual pieces of armour can be attached, you could take a look at the online shops which target medieval enthusiasts and re-enactors.
Visit the site below, and look for individual pieces.
While, this is strictly speaking not totally, historically accurate, it should give you a good guideline of how it can work.
Plate armour section from a German shop, which shows some of the individual pieces in the context of the wearer. There are plenty of other online shops, which offer different pieces and styles of armour.
Here's a loose list of informative YouTube Channels, feel free to expand the list.
This channel is thematically dead-on if you look for information regarding plate armour and everything that goes with it, i.e., the soft kit underneath, maintenance, etc.