Expedition 1 in 2000 was the first long duration stay on the International Space Station, but in 1998 the construction of the station began, with several spacewalks and using Space Station Remote Manipulator System (SSRMS) installed on the Space Shuttle used to assemble and prepare for operation first three ISS modules, Russian Zarya and and Zvezda, and American Unity. Quoting Wikipedia on International Space Station, Assembly:
The assembly of the International Space Station, a major endeavour in
space architecture, began in November 1998. Russian modules launched
and docked robotically, with the exception of Rassvet. All other
modules were delivered by the Space Shuttle, which required
installation by ISS and shuttle crewmembers using the SSRMS and EVAs;
as of 5 June 2011, they had added 159 components during more than
1,000 hours of EVA. 127 of these spacewalks originated from the
station, while the remaining 32 were launched from the airlocks of
docked Space Shuttles.
The first module of the ISS, Zarya, was launched on 20 November 1998
on an autonomous Russian Proton rocket. It provided propulsion,
attitude control, communications, electrical power, but lacked
long-term life support functions. Two weeks later a passive NASA
module Unity was launched aboard Space Shuttle flight STS-88 and
attached to Zarya by astronauts during EVAs. This module has two
Pressurized Mating Adapters (PMAs), one connects permanently to Zarya,
the other allows the Space Shuttle to dock to the space station.
On 12 July 2000 Zvezda was launched into orbit.
And this is how the ISS looked like when occupied by its first, Expedition 1 crew in 2000:
International Space Station photographed from approaching STS-97 on 2 December 2000 (Source: Wikimedia Commons)
More about the assembly of the ISS is available in the Wikipedia link.