Anyone any idea at hougang ave 8 if there is a function room of any place that I can celebrate my lo's birthday?

Not sure what is the group size or budget you are looking at. You can consider TIckle Tickle (but they are located at Hougang Sportshall - 93 Hougang Avenue 4, #01-04, Singapore 538832). See image for there rates (for 8 pax). Taken from their website: http://tickletickle.sg/services/party-bookings/ Or perhaps you can consider booking a multi purpose room at Hougang CC: https://hougangcc.org.sg/pdf/facilities.pdf (but also not at ave 8, unfortunately).

See if there is any condo nearby that you have a friend staying there or alternatively, think you can book the community club as I think not too expensive. You can also try to check it out with McDonald's as I believe they do parties as well.

You might want to consider MacDonald, multi purpose hall or even under the void deck. They are more cost effective.

U can hold parties at the multipurpose hall. Rent from the town council. :)

Multi purpose hall is a good option.