I've never tried to memorize an English word.

In addition, my memory is bad now, memorizing any English word is very difficult for me.

So as long as I see an English word and know what it means, that's okay.

Could also say 'and I know what it means'

When I writtype in English, I only need to input the first few letters, and then, the related English words will pop up on my keyboard for me to choose.

Writing is used for physical writing. Typing is used for keyboards.

If the word that I want doesn't pop up, I probably inputtyped the wrong letters, then I will read the word so the word will pop out.

While input is not wrong people usually say 'typed' or 'put in'

If I failed in both of the methods, I would use the translation apps on my phone, putting in the Chinese words to get their corresponding English wordsEnglish equivilant.

Equivilant is a noun that means 'an equal substitute of something else'. In this case, your are getting an equal translation of your Chinese words in English.