去加拿大(多倫多)過關

I can't type Chinese so if you need translation, you might try Google or such source.
1. CBSA (Canada Border Service Agency) agents will ask you what's your purpose for the trip (to visit relatives) , for how long (3 weeks) , if you have any goods to declare (ie. tobacco, liquor, etc) and if you have enough funds to stay
2. You are not required to have visa to visit Canada if you hold BN(O) or HKSAR passport, thus, there's no requirement to show any prove from work. Generally, you will be granted 6 months of stay in Canada if you satisfy the CBSA officer that you intend to leave
3. Either Permanent Resident or Canadian Citizen depending if he have received citizenship.
4. Getting married in Canada does not require a visa unlike the UK and because getting married won't get you citizenship or PR status unless your partner sponsor you, it will not affect your admission interview.
5. Generally speaking, you must have a 2-way ticket available before you enter Canada. However, it is up to the CBSA agent to determine to grant how many months you can stay.
6. If you can't answer questions in English, to the satisfication of the CBSA agent, you will be directed to secondary screening where translation will be available.

首先, 由香港飛往加拿大, 清關的地點, 是溫哥華。其次, 年齡和性別, 加拿大政府的政策上, 基本是一視同仁, 不用在這方面擔心。
回到問題上,
第一, 由於 (1) 、(4) 和 (6), 某程度上, 是過海關的, 一併作答。請留意, 若英語能力不太好, 應在過海關的時候, 要求識中文的翻譯員, 否則, 後果難料。另外, 單是探親 (舅父一家)的理由已足夠, 無謂增加其他變數。
第二, (2) 這個是増加被拒入境的機會。
第三, (3) 你的舅父的身份, 可能是居民, 也可能是公民。
加拿大的居民和公民的分別?
加國的公民, 享有投票選舉的資格, 同時, 可持有有效的旅遊証明文件 (PASSPORT);若在國外, 可受到加拿大領事館的保護權。而居民的身份, 是沒有投票權, 沒有加拿大政府所各簽發的 PASSPORT, 此外, 有可能得不到領事館的保護。
居民成為公民, 有兩個條件, 1.) 住滿所需年期, 如五年內, 需不少於三年在加國居住；2.) 通過入藉試。
第四, (5) 如果沒有有效的回程機票, 被拒入境的機會很高。
希望以上的解說, 可以幫到你。

(筆者, 加拿大公民, 居住多倫多)