How do I remove widgets(?) from my homepage

Hi there,

I was wondering if anybody could help me. My web designer customised my wordpress for me but he specified that he did not want to get involved with further help afterwards. I was wondering whether you could help me alter my website a little? Here it is:
https://thepeoplestories.co.uk/

I want to get rid of the ‘jobs’ tab at the top right on the homepage, I can just delete this Page can’t I? And I wanted to delete the ‘jobs’ feed right at the bottom of the homepage as well as the twitter feed. I think the twitter feed is a widget (although I’m not very sure what one of those is!)

I was wondering whether you could shed some light on what I have to do to remove these? Do I go into my ‘Editor’ in the left hand side of my dashboard? So sorry, I have never done this before, complete beginner! Can I literally just delete the code or are they plugins/widgets that I can just remove? Any help would be very very very much appreciated!
Thanks
Roz