Lubricated condoms can be icky, yes. Which is why we generally recommend unlubricated condoms plus a water-based lubricant of your choice.
I do hope you're still using condoms if you're still having sex, though... safe is MUCH better than sorry.
As for how much lube to use? Depends on the person and the lube. Some folks like lots of butter on their toast, some people like a little, right? Same with lube. Use enough to make things feel nice and slippery, and if you need more, you can add more. Some lubes stay slippery longer than others, so depending on what you're using, you might not have to use as much. In general, a small amount will do at least for starters, enough to spread a thin coat over the condom-covered penis, and a thin layer over the entrance to your vagina (maybe also your clitoris and the rest of your vulva too if you want).
The only real exception is anal penetration -- most people want, need, and will use considerably more lube for anal penetration because the anus does not self-lubricate the way the vagina does during arousal.
Otherwise, use as much as feels good.
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