When you have a look on the command line on the bottom, LibreCAD tells you what to do.
Use Create Block and the command line ask you to select entities for the block to create.
Please note the selection tool bar to the left. Use one of the tools from the tool bar or simply click on the entities.
After finishing selection press ENTER or click the button on the bottom of the selection tool bar, with the double arrow pointing to the right.
Now the command line ask you to specify the reference point for the block and the cursor becomes the dashed cross.
Click the reference point for the block or enter the coordinates on the command line.
Then you are finally asked for the block name. Assign a name for the block and confirm it by clicking in OK.
That's all.
Armin
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