Sql linked list

Hi y’all.

I’m having trouble getting my head around this.

i have a table:

tbl_test
fields: id, text, parentid.

parentid is a reference to id in the same table.

entries could be:

1 | sometext | -1;
2 | sometext | -1;
3 | sometext | 1;
4 | sometext | -1;
5 | sometext | 3;
6 | sometext | -1;

what i want from a query:

give me all entries that have a link to record 1 trough the parentid.

so from the list above i would want:

1, 3, 5

I have no idea how to do this can anyone point me in the wright direction?
thx…