There is definitely surgery which can help this if it's required.
But for a vast majority of men on T, their facial structure appears to change enough to prevent the need for it. The muscles in your face will thicken, and the fat around your jaw, and some around your cheeks (typically) will thin, allowing your face to appear more 'chiseled'.
If you find after being on T for a few years, that you do need this surgery, there are some options available, just like you can find plastic surgeons who will attempt to do almost any procedure. Things like widening your jawline/chin are definitely doable, as are almost any number of nosejobs imaginable. But I would be VERY careful when researching these, as FFS is done often enough where there's quite a few options for it, facial masculization surgeries don't seem to be as prevalent, so you might have to dig a bit to find the best options.
And if you have men in your family who grow facial hair, you might not need anything to modify your chin/jawline after some time on T, depending. Some guys with very thin, or feminine faces can get away with trimming their beard specific ways to make their faces seem more squared off.
Noting of course, this is assuming you haven't been on T, or are only just starting it.
