You've asked a lot of questions about how you can get STDs.
The only way to get STDs are:
* oral sex - your mouth on someone's genitals, or their mouth on your genitals
* direct genital to genital contact - this is unclothed vagina to penis, penis to penis, or vagina to vagina contact. If penetration isn't involved, some intense rubbing and grinding without clothes on needs to happen.
* anal sex - penis in the anus penetration
All of these require clothes to be off of all people involved, and condoms reduce the risk of STDs either totally, or significantly, depending on the STD.
Nothing about breasts transmits anything, unless you are a baby and breastfeeding, and handjobs and fingering are safe (hands never transmit STDs).
If either or both (or all) have clothes on, even just underwear, STDs can't be transmitted by humping/grinding/rubbing.
Dry humping is not a risk for any std.