If you have a degree then you are in the favourable position of being at the top of the list for entry level, internships, graduate roles, and many service level jobs. You will be ahead of people with Diploma certificates, unless the person with a Diploma has some good relevant work experience to balance their resume out. You are also ahead of people with no certificates.
If you have a degree, some work experience anywhere, a good resume, then you will find work. It is usually very much favoured upon by HR and medium-big companies. You are ahead of many other unemployed people. Essentially a lot of companies want either degree educated or good 2-5 years of work experience in that industry.
I don't have a degree, I have a diploma, which is generally 2 years of education not 3-5 years like a degree is. But I am still getting interviews because my resume is really nice. Has some cool formatting. I have some work experience to combine with education certificates.
Keep trying, you'll get something soon.
If you've gotten through university, then you are already well trained to do well as an intern or an entry level.
You could also apply for some retail, so that you develop customer service experience. Any job is hard for the first few months, but the experience would be valuable. If you get into retail or hospitality then it would help for when you get an internship for dealing with team members, clients, managers. Interaction and politics can be a powerful presence at professional workplaces. That can be a bigger challenge than the actual work. Dealing with the people.
Good luck, keep trying. Remember that if you do get a job, you may like it or dislike it, you can always leave and get another one at some point. You aren't locked into anything. This is the great thing. Companies interview you and give you a 3 month probation, but you can also do the same. So if you get any sort of work, use the same approach. You give them a 3 month probation, see if you enjoy the environment, the people, the work, the location, the travel. Because you can always stay or go.
Remember that when you think about interviews and new workplaces being a nervous anxiety filled thing. You can leave if it truly isn't a match for you.
From what I've noticed. Lots of people make mistakes at work, but they hide it well, or they don't make it obvious. I've worked with people who were really low on knowledge and so I did my best to train them. I really enjoy training people so they feel better, there is nothing better then helping people with knowledge to make their life easier. So when you do get a job there will be people who are struggling more than you realise, but they may be hiding it very well. There will also be the super-confident ones who have been technicians for years and will show their ego, but the more exposure to them the better you will feel dealing with them.
My advice is to give it a go. Apply for jobs you want and give yourself a chance. Because the majority of the workers will be feeling just like you, unsure, nervous, under pressure, uncertain, motivated, maybe a little excited. See it as an experiment to test yourself. Whatever the outcome.
If an outcome of a career is good or bad it's still building up your skills muscles. Better than sitting around not getting any experience.
Try looking for company websites job sections as well as general graduate job sites. So you'd need to research the big companies that hire graduates. Maybe give yourself a target 5 applications a day. 2 in the morning, 2 at night and 1 at lunch, so you keep a consistency of application at a good level that doesn't take up your whole day.