Hi rio.matthew,
One way would be to use the Constrains from the Object Manager>Tags>Character Tags>Constrains. However, I’m not really happy with the option of the set up for your question here.
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So, I created an XPresso tag for you, which you can save as File>Save as/Load as Tag Preset…
This Tag has User-Data. You drag your Spline into it and set the point number with the slide, or type it.
Thats all. (Perhaps if you need to animate that, check the priorities [Tag selected: Attribute Manger] if you find that the position change is a frame to late.)
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Let me know if that works of if there is something else, I’m happy to have a look into it. MoGraph comes to mind, but way more clicks to get something working—for this set up.
All the best