Edit the width of featured images

Hi
I have a problem in the way titles are displaying underneath my featured images, Some images are not aligned with the titles beneath them.

Could you take e look and advise me hw I could best remedy this> Not sure whether the option would be to change the default settings for the featured images.
If so , how can I do that?

Or can I adjust the titles so that they align to the image width.

I would also like to increase the space between the image and title.
Hope this makes sense. I will post login details below