What tools and platforms do you recommend for providing a hands-on coding experience in online lessons, ensuring students get practical exposure to writing and testing code?

There are different tools that vary from language to language, As I am familiar with Latex and Python, I usually suggest these platforms: 

Overleaf: For Latex we have different software environments and editors for example MikTex and textstudio, but in my lessons, I suggest students use Overleaf because it is an updated editor which is updating on a daily basis, while in the case of software environment, we have to update them manually or sometime we skip the update due to which we had errors later on. 

Apart from this if students get any error I can monitor them through Overleaf as it is a collaborative tool, I can debug easily and guide them properly in this case that's not possible for the software environment. 

Google Coolab: As for Python I will suggest Coolab, as it is a notebook environment and gives you a better graphical interface to understand the code for beginners. for the beginners it's easy as you don't need to install libraries manually.