IS MARRIAGE COMPULSORY IN ISLAM?
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Depending on the situation, the ruling of marriage will vary.
In general circumstances marriage is considered a sunnah (prophetic practice). One is encouraged to marry and start a family. (Rad al Muhtar)
In the situation where one fears falling into sin (adultery or fornication), then marriage becomes obligatory (wajib).

One is recommended not to marry in the case where one is terminally ill, feeble or unable to fulfil rights associated with marriage. (Fiqh al Halal wa al Haram of Shaykh Khalid Saifullah Al Rahmani)
“Arrange the marriage of the spouseless among you, and the capable from among your bondmen and bondwomen. If they are poor, Allah will enrich them out of His grace. Allah is All-Encompassing, All-Knowing”. (Qur’an 24:32)

“And those who say, “Our Lord, Give us, from our spouses and our children, comfort of eyes, and make us heads of the God-fearing.” (Qur’an 25:74)
Most prophets had family and children:
“We have sent messengers before you, and gave them wives and children.” (Qur’an 13:38)

"O group of youth, those of you have the means, should certainly marry.” (Bukhari and Muslim)
It should also be noted that your partner is definitely known to Allah and these are matters that are recorded in advance by Allah. A marriage partner is part of your rizq (sustenance) decreed by Allah. Our job is to make the efforts to find a suitable partner, there after leave the matter to Allah.
“Indeed, all things We created with predestination.” (Qur’an 54:49)
“All things are from Allah.” (Qur’an 4:78)
And Allah knows best.