Sleep thru the night. Possible?

Baby has full of fun filled activities! My baby is now 7 months. I am planning to sign him up for little gym classes so he can enjoy the exercises there. I think he has plenty of exercise when he crawls but he does not do that often. He prefers to be on the walker! Is that strange for a 7 mth old boy?
What he can do is:
* crawl a bit, especially when there’s peer pressure!
*glide on the walker!
*stick out his tongue and lick his lips.
He is still waking up in the middle of the night! Well, my guess is because he does not have enough food during the day, but nowadays I try to give him more water at night. He won’t take more milk than he can drink and usually drink lesser milk nowadays. However, there are some tips that baby center says:

Your child is old enough to start sleeping through the night. The key to making this happen is establishing a consistent bedtime routine and developing positive sleep associations. Seven-month-olds should nap two or three times a day at approximately the same time and go to bed between 7.30 and 8.30 at night.

Babies love routine, especially ones that happen around bedtime. You can first bathe her and change her into pyjamas, then breastfeed or give her a bottle. You can top the night off by reading a bedtime story (pick one or two stories that you'll read every night) or sing a few songs (choose a set of tunes for bedtime). By doing the same thing night after night, you will be letting your baby know that it's time for sleep.

To teach your baby how to fall asleep on her own, put her down in her cot while she's still awake and periodically check on her. Within a few nights, she will be falling asleep quickly and easily at bedtime. Once she is able to soothe herself to slumber, she will inevitably begin sleeping for longer stretches, and eventually, all night.

Until she learns how, respond to her the way you usually do when she wakes up in the middle of the night.