What happens with UC if you just don’t get any job you apply for?

[Subjective]

If you’re doing the work searching , attending interviews and meeting all commitments what happens when after a prolonged time you still haven’t got a job ? They can’t sanction for this can they but what do they do?

Nothing...... as long as you can prove you are actively looking.

Nothing.

That’s the point of the welfare state. You are actively seeking meaningful employment to contribute to the economy and have a better standard of living.

If the jobs aren’t there that’s tough for you - why would you be penalised by having no income?

Nothing, as long as you are doing the commitments set out.
are you personally in this situation?

i would hope that some guidance is offered re making sure your cv, cover letter and interview performance are all of a standard that will maximise your chances of finding work. Have no idea if this is actually offered, but it would seem sensible.
from a financial perspective no penalties. It’s tough enough looking for work and imposing financial penalties would make the process even more stressful.

As above, as long as you're adhering to your Claimant Commitment for job search and anything to improve skills etc you'll be fine.

Are you getting feedback from employers and can JC+ staff provide any guidance.

They can't do much if you are meeting your claimant commitment. Eventually they may refer you to a programme that aims to get people back into work.