Today I will try to give you some fun projects to work on in your free time. I personally think that these little projects will definitely help you improve your knowledge.
The purpose of these projects is to face new problems and troubles that you will be able to face throughout your dev career.
Why RESTful API? For me personally, building API's helped me get to know the backend aspect and what it actually takes for your data to get to your fetch request. You can have a lot of fun building these. I recommend making simple CRUD API's for example Jokes API that you can call to get some jokes and you can also put in a cool random get request that gives a random joke to the user that is fetching. I made one of my own using Vue.js for frontend, node.js combined with Express.js and MongoDB. You can check it out: Random Programmer Puns.
Building blogs is time-consuming but the end result will always make you happy and proud of your result. Building a blog will take you to combine the RESTful API I mentioned above and a frontend which will be your glue. I suggest using Vue.js or React.js for creating the frontend but you can also use other frameworks or no framework at all! You can also make your blog use markdown just as Dev.to does! This is a really cool project to use especially to add to your portfolio or your CV. It will combine all of your skills!
Creating complicated website layouts is tedious but in the end, it will make you ready for real-life projects that you will face. You can take inspiration from dribble designers, design it yourself, or take part in an HTML & CSS challenge. You can also brush up on your SCSS knowledge by combining a lot of mixins to save your time.
This is all that I've prepared so far. I hope that you liked the idea behind this post. I love talking about code and being connected to people that like talking about it too!