There are many ways if it is macroscopic and not airborne.
We probably could recognize life in the clouds of Venus,
if there is some, but it is difficult to explore there.

Uhm... I have to disagree there. Life modifies the environment (see
current geological theories regarding influence of litho bacteria and
formation of ore deposits). I think we would spot the little devils
even if they aren't macro.

Do I believe in life elsewhere? You betcha!
Where do you think we came from?
Umm, if you're suggesting exogenesis, that simply pushes the question back
to "where did that life evolve from?"

There is no difficulty with a scenario which will lead to
life from natural chemicals. We can now duplicate most of
the process. We can create "life" from inert chemicals now,
but it is easier to use products of cells to do it.

No "we" can't create life yet. Just the building blocks (aminoacids).