Yes, but that’s not the case in all or even most countries. In my country most constitutional amendments can be made by a two-thirds majority in the legislature. Usually this involves the government coalition negotiating with one or more opposition parties to vote with them.

Of course there are other countries where there is no constitution (in the sense of a supreme law that other laws are subordinate to and can be struck down by the courts if they don’t comply with it) at all, e.g. the UK.