26, knee oa - meniscus tear/ scope surgery 10 yrs ago - was ncaa athlete. Drs say distal femoral osteotomy. Can I improve my alignment w/ pt instead of surgery? Now low impact lifestyle and no pain

Somewhat. Yes, i would maximize physical therapy and an "unloader" knee brace, customized for your misalignment. This brace provides some realignment to you while weight-bearing. If you fail to see satisfactory results with conservative management, then an osteotomy could be helpful for you. Keep your weight at a healthy level, as this may be the #1 modifiable factor to prevent progression of your arthritis.
You may be able to. Achieve a minimal amount of alignment improvement with pt. However, this degree is likely insignificant.