@kediskep, this is what Mayo Clinic says about treating multiple myeloma:
"Multiple myeloma treatment isn't always needed right away. If there are no symptoms, you might have tests to watch the myeloma to see if it gets worse. When multiple myeloma causes symptoms, treatment often starts with medicine. Treatment can help relieve pain, control complications, and slow the growth of the myeloma cells.

Sometimes multiple myeloma doesn't cause symptoms. Doctors call this smoldering multiple myeloma. This kind of multiple myeloma might not need treatment right away. If the myeloma is at an early stage and is growing slowly, you might have regular checkups to monitor the cancer. A health care professional might test your blood and urine to look for signs that the myeloma is getting worse.

You and your health care team might decide to start treatment if you develop multiple myeloma symptoms."
Read more https://www.mayoclinic.org/diseases-conditions/multiple-myeloma/diagnosis-treatment/drc-20353383"

It sounds like you need answers from medical professionals to your very valid questions. I would ask things like:
- Since I have do not have symptoms why do you recommend treatment right away?
- What might progression look like for me if I chose not to do treatment immediately?
- Does my myeloma have any high-risk features?
- What are the goals of treatment for me?
- What are the possible side effects of treatment?
- If the first treatment isn't successful, what will be the next option?
- What is the outlook for my condition?

I'll be interested to know what you learn.