Sony A7R IV has a Sony E lens mount and currently there are 184 native lenses available for this mount.
A7R IV also has a sensor based image stabilization system which means that all of these lenses will be stabilized when used on A7R IV.
Since Sony A7R IV has a Full frame sensor, it has a focal length multiplier of 1x so lenses will provide their original focal length on A7R IV.
You may also also be interested in these:
Sony A7R IV Lenses with Image Stabilization
Sony A7R IV Lenses with Weather Sealings