How to see free space in a table in Postgres after going through an auto vacuum process?

Question

PostgreSQL

Good afternoon!
Tell me if it is possible and how to see the amount of free space inside the postgres table after it is cleared by the autovacuum process.

There is a certain table, many insertions and deletions were made in it in a short period of time (there are more deletions). After that, the autovacuum process came and removed the dead tuples (dead tuples). There is a great desire to make Full vacuum, but before that we need to understand what we can get after that, whether the space occupied by the table will decrease and if so, by how much.
We use PG 12

Answer 1

pgstattuple + this query