How to find and copy a bold line in word, and then change the selected lines?

Question

Macros

Good day!
There is some Word document in it there are lines/paragraphs in which there are words highlighted in bold.

Help with writing a macro, namely:
1) it should copy the line in bold,
2) paste the copied copy of the line immediately below it,
3) in the copied copy at the very beginning of these lines / paragraphs, add / put the sign = (equal)?