I can offer at least two point of view.
The first is that what I thought was massive social anxiety was actually just social inexperience, that is a large part of my anxiety derived from not knowing what was the accepted social protocol in a given situation. Usually sitting quietly and observing what others did helped.
The second is that you need to subdivide and identify which steps of social interactions you are able to do and which you aren't. For example, instead of just throwing yourself into a social gathering, you can (for example) get ready and go out from your house, but not get in front of the place. Or you can get in front of the place but not enter. Or you can enter but you have a sense of urgency that prompts you to leave immediately after, etc. Instead of "just practice" the whole interactions, identify the smallest next step that you can practice, and if you can't practice that step, subdivide into even smaller units (e.g. literally just doing the next step).