Hi @hendy_5450,
Thanks for sharing the screen recording. I see what you mean about the spacing shift when bolding the text. This usually happens if the bold style you're applying is not from the same font family or if there's a faux bold being used instead of a true bold weight.
Can you please confirm the name of the font you're using and whether it's activated from Adobe Fonts or installed locally(share the developer link)? Also, let me know if this happens across different fonts or just with one specific typeface. Try selecting the text and applying the bold weight from the Character panel instead of using the Bold button or shortcut, and see if the spacing behaves better.
Looking forward to hearing what you find.
Abhishek