A doctor who does dive medicals is exactly who you need to see. They will be able to assess whether you are fit to dive.
I actually dived 5 weeks after my surgery! My breast surgeon was so excited for me - she is also a diver and was completely happy for me to do it. I had to delay my chemo for a few days as I didn’t get back in time for my original start date. The oncologist laughed when I explained why and said that’s a new excuse.
Then I dived again 3 months after completing radiation (5 months after chemo) I had a full dive medical for this as I couldn’t get travel insurance without it. I did have a bit of peripheral neuropathy in my feet from chemo but it didn’t cause too many problems. The main issue I had was making sure I didn’t get sunburnt as my rads area was still a little sensitive. But that would have been more of a problem if I was just relaxing by a pool.
Have a great time!