It is possible, but it is not advisable. You need to enclose the column name in double quotes.
create table my_table ("MY COLUMN" number);
But note the warning in the documentation:
Note: Oracle does not recommend using quoted identifiers for database
object names. These quoted identifiers are accepted by SQL*Plus, but
they may not be valid when using other tools that manage database
objects.
The name will be case-sensitive, and you wil have to enclose the name in double quotes every time you reference it:
select "MY COLUMN" from my_table;
So… don’t, would be my advice…