I'm enthusiastic about being able to read, write & speak English like a native speaker.

I'm guessing you mean you are excited to acquire those skills. If so, this would be correct.

I am here to do continuous writing practice as wellI asm excited to learn about foreign culture from real humans instead of talking to some AI bot :-P

This is one correct way you could connect these sentences together.

I'm keenthusiastic to read, write & speak English like a native speaker.

I am here to do continuous writingly practice my writing as well as excited to learnlearn about foreign culture from real human being instead of talking to some AI bot :-P