From the text (very end of the bill):

180 days after royal assent

(6) Despite subsections (1) to (5), any provision of this Act that does not come into force by order before the 180th day following the day on which this Act receives royal assent comes into force 180 days after the day on which this Act receives royal assent.

The bill received royal assent on June 22nd, 2023, which actually means this law takes effect in December at the latest.

EDIT - I think we were updating our messages at the same time as I added the above before yours was finished.

I think it's clear that Meta would be covered if it links to news given this section:

This Act applies in respect of a digital news intermediary if, having regard to the following factors, there is a significant bargaining power imbalance between its operator and news businesses:

(a) the size of the intermediary or the operator;

(b) whether the market for the intermediary gives the operator a strategic advantage over news businesses; and

(c ) whether the intermediary occupies a prominent market position.

7 (1) If this Act applies in respect of a digital news intermediary, its operator must so notify the Commission.

There's doesn't seem much room for Meta here - if they link to news they'll be covered by this law. The only possible escape might be in Section 11 where it allow the Governor in Council to write regulations that exempt organizations, and if the government is going to exempt Meta they might as well just repeal the law.