Lubricant. Over the counter lubricant k-y jelly is the best.
Water based. Any water based lubricant is fine. 2011 study noting increased HIV w/ water based lube raised concerns, but water based lube is better than oil based because oil can damage condoms so for now, we still recommend water based lube with condoms. Spermicide lubricant with nonoxynol-9 may increase risk for HIV slightly so avoid. Be safe by using condoms& know your std status (and that of your partner).
Water-based. The only lubricants that are safe with condoms are water based lubricants. These can be found in any drug store and should specify that they are safe for use with condoms. Non water-based lubricants can break down condoms and this could cause infectious agents or sperm to break through.