Frameworks can be hard to learn. Having to memorize all shortcuts and styles makes it feel like you are learning a new coding language. It can take a lot of time to understand it and memorize what to do. The first framework I learned how to use was Bootstrap5. It is used in html and can make it so you do not need a style sheet. Of course you may not be able to 100% get rid of the stylesheet but after using Bootstrap5 my style sheet only had a couple lines. One big part of Bootstrap5 is the container. It was difficult to get used to learning how to put row and column classes in the right places. I think it was important to start using frameworks right after learning html because when I was learning bootstrap it was hard for me to get the syntax right so I automatically wanted to just start using css more which in turn made it take longer for me to code a website as bootstrap does cut down a code by a lot.
Like I mentioned earlier, once you get used to bootstrap it can save you a lot of time since the code is significantly shorter which in turn can mean it is less likely for you to make syntax mistakes. Having container makes the style sheet a lot shorter since container does a lot of the display work. Since you do not have to code so much of the display on the stylesheet it gives you more room to play with more characteristics that will stand out like changing the color or fonts.
Though bootstrap makes the style sheet a lot shorter I noticed that when using bootstrap I had to use div a lot more. Using a lot of div can make the code seem unorganized and can make it difficult to notice the difference between all the div however if you also have coding standards implemented into your idle then having a lot of divs would not be an issue.
There are a lot of Frameworks other than Bootstrap however I have only worked with Bootstrap so I can only speak for Bootstrap but Frameworks can make your code more organized and shorter. Think of frameworks as a shortcut for web developing. For front end coding separating the display from the style sheet can mean that you can be creative in the style sheet.