how to import solidworks file into catia?

try and use the .STEP file format to transfer the Save the data. Solidworks assy as .Step. and then Import it to Catia. this will ensure that your tree structure is maintained.
For Catia Product you can Save it is CATproduct and not as CATpart. so save the same and all the related components will save.

but the problem is that i do not have solid workss software

SAVE YOUR SOLIDWORKS FILE AS .stp
and open from catia it will automatically converte and then you can save your file as
.catpart

I am totally agree with the comment below, try to use .step or .iges

is the best way.

Regards,

mmm this is a problem of catia, catia cant open sw files ,im don know why ,maybe is enginering be a tarados.

First mentions which software you have

But the part is not opening in assembly of catia