It's not important what we think about the website. It's important what the client for whom you made it thinks about it. And surely you let him approve your design and prototype, didn't you? That is, assuming the old-fashioned linear development. Nowadays, it's more agile and interactive, allowing for daily feedback about your work. And all of that should result in a website your client thinks marvellous.

In general there are many things you can do to speed up a website. Google is a great help if you want to know more than you learned at school. Moreover, we had a few recent discussions about in our web development forum https://www.cnet.com/forums/web-hosting-design-coding/ , like https://www.cnet.com/forums/discussions/how-to-increase-website-loading-speed/ and https://www.cnet.com/forums/discussions/website-speed-issues-should-i-change-hosting/ .

And isn't the idea about a traineeshop that your are trained by the company, your supervisor and your colleagues?