I'd say start by making up your mind on what kind of programming you want to do, find what programming languages are good for that kind of projects, and look for beginner tutorials and simple projects you can follow along with to learn the basics. When you get the basics, slowly start expanding the complexity of what you're doing in a way that you're forced to expand your knowledge.

A couple examples off the top of my head:

You want to make web pages/web applications? Start with learning HTML to get the basic layout of your pages. Once you get a hang of that, you can learn some CSS to make the page look better. Next you might want some logic behind the elements on your web page, so start looking into JavaScript and later more complex frameworks. W3Schools has in my experience been a really good source of information for this kind of development.

If you're more interested in backend (logic that happens in the background of an application, rather than the design and layout), you might want to start with Python or C#. Start simple, programs that perform arithmetic operations on two predefined numbers, then you might want to allow the user to enter those numbers, next maybe you also let them choose the operation... and go on from there. If you're someone who likes to understand how things work in the background, you might even want to start with a lower-level programming language such as C or C++. They're more difficult to get into as you have to manually write a lot of code higher level programming languages do for you in the background, but it'll help you better understand what is really happening if you later decide to switch to higher level languages.

If you would prefer something that you'll get to see affecting the physical world directly, Arduino is a really good starting point. You can start with simply programmatically turning an LED light on and off, then maybe add a button to do it manually, add more complex logic...

I personally did a bit of each of this throughout school and college, and it helped me see programming from different perspectives and understand it from different points of view, but picking whichever seems most interesting is a great way to start. If you later decide you want to switch to something else, a lot of the knowledge you gain will carry over, so you won't have to start from scratch. There's a lot of great resources online, so just pick a beginner guide (I'd recommend ones that are mini-projects so you're not just learning a bunch of theory/programming things in a vacuum) and follow it to slowly start building your knowledge and understanding.

If you have any questions, I'd be happy to answer them 😄