Not advisable as once you start treatment your body's natural testosterone production will shut down and you'll be dependent upon testosterone patches for the long term.
If your testosterone is still within the normal range chances are the deterioration in the quality and duration of your erections could be a result of cardiovascular issues rather than be hormonal in nature.
There are many way to improve both cardiovascular health and testosterone levels at any age but it requires effort and dedication on your part.
https://vitylman.com/nz/10-easy-exer...your-erection/
https://www.healthline.com/nutrition...erone#exercise
With a bit of dedication you'll find out what works particularly well for you. In my case I found that boosting NO levels resulted in significant gains in sexual performance. I now add beetroot juice, kale powder etc to pretty much everything!!!