Rendezvous and Docking

Here is an ESA documentary on how crews flying the Russian Soyuz spacecraft get to the ISS using what is called Rendezvous and Docking

Soyuz rendezvous and docking explained

Soyuz has a toilet in its habitation module.

Rendezvous is carried out in two distinct parts followed by an automated docking to the ISS

• The Phasing orbit

• Bielliptic Transfer

• Docking

The SpaceX Crew Dragon and also Boeing's Starliner will also use similar rendezvous and docking profiles