How can I prevent all known languages like C# and python from getting mixed up?

Answer 1

schedule them.

Answer 2

By learning and practicing each one at different times ^^
Learn a new language only after be well skinned on previous, focussing only to once ;)

Answer 3

each of them has characteristics that are different

Answer 4

i would be more worried about forggeting stuff as getting mixed up is hard

Answer 5

they all have different APIs and each API comes with syntax recognition for that particular language, eg when coding in C#, it will not recognise Python syntax or language