Hello,
How about turning on dimension snaps? I attached the link so that you could check.
Manage > Snaps
https://lazybim.com/revit-snaps/
Please mark this response as "Accept as Solution" if it answers your question. Kudos gladly accepted.
Ei Zin Myat
Technical Sales Unit Engineer
ONESTRUCTION Co., Ltd.
eizinmyat@onestruction.com