Hello everyone. 
Is it possible to constrain the minimal increment to a specific distance?
 2 mm for example; So each time I draw a line with Bezier tool I get I multiple of 2. Thank you so much.

I´d try Extensions->Modify Path->Add Nodes… in the end.

Thank you for your response.  I managed to add more nodes, but I can't see any parameter to set the distance between nodes. Thanks 

There's no setting to restrict line segments to an incremental length.

Maybe you can use grid snapping.
[Enable Snapping] [Nodes ☑] [Cusp Nodes ☑] [Grids ☑]
[File > Document Properties...] [Grids] [Rectangular Grid > New] [Grid units: mm] [Spacing X: 2] Spacing Y:2]

This only works for orthogonal lines. If you need other angles you could rotate your shape or rotate the gridlines.

Alternatively you could draw a 2mm line and build your shapes by pasting and rotating copies, then combining these into a single shape.

Thanks a lot. I'll try .

"Maximum segments length" works here:

Thanks a lot, it was helpful.

Thanks Polygon. I forgot about that extension. It works for curved paths too.

[Extensions > Modify Path > Add Nodes...]