That's hard to answer. The CDC says undetectable equals untrasmitable but HIV is only 1 of many sexually transmitted diseases and several now resist known treatments. This is not medical advice just my opinion. I personally would use protection. After I've been in a committed relationship I would still use protection for I was in one when I contracted HIV a friend who I had known for over 20 years and was with for several years.

No, how do you know your undetectable for sure you viral load can fluctuate. You need to be on you meds and know your undetectable. and your partner on PreP and then the Dr will give you the green light. You should always use protection till then because your exposing your partner.

yes, you can..but not advisable...U=U means... if you are undetectable you are untransmittable.
U=U...The evidence is in: If you are HIV+, take treatment and maintain an undetectable viral load, you can have sex knowing that you won’t pass HIV to your sex partner.
In short, when HIV is undetectable, it’s untransmittable.
https://www.catie.ca/en/positiveside/summer-201...

However, you can still catch STDs (sexually transmitted diseases...such as syphilis, gonorrhea, genital herpes, hepatitis ) and they are on the rise!!!

Thebody.com is another great place for answers. U =U has two different long term studies to back it. Undetectable equals Untransmittable. This is from the last Infectious diseases conferences.

I enjoy it more.