I went to have a drink with my girlfriend to in Ueno. There are a lot of watering holes. All the/many/some waiters working there are foreigners but they're fluent in Japanese. We had great time there. I would I'd like to be fluent in English as they speak are with Japanese.
I got a little drunk.

Overall, it's clear what you mean.

Some alternatives for the first sentence:
I went to Ueno with my girlfriend to have a drink.

My girlfriend and I went to have a drink in Ueno.

I went with my girlfriend to Ueno to have a drink.

Please correct my post more precisely or naturally

I went to Ueno for a drink with my girlfriend. There are a lot of watering holes in my city. The waiters working in these places are usually foreigners , but they are fluent in Japanese . We had a great time there. I would like to speak English as well as these foreigners speak Japanese . I was a bit drunk .

Sorry for the mistakes in my writing.