Is it possible to forget previous languages as you learn other new ones? If yes, how can this situation be avoided or handled?
If you learn too much at once, you can get all of them mixed up, but I think if you practice all of them, there won't be problems like that. I suggest to do challenges on all languages you learn regularly
surely... practicing all of them can help with this as @Airree said. but also... If you forget.. then google it. :)
The way to avoid it is by going back and coding in your previous language.