Unless there’s some sort of crypto swap service that supports Lightning, you’ll probably need to trade it for BTC and open a new Lightning channel (or splice it in using something like Phoenix wallet)
Depends ultimately on what you’re looking for: do you want self custodies sats on the Lightning network, or are you ok with custody tradeoffs?
(Tbh I know nearly nothing about litecoin, but if there’s anything I can do to help a fellow pleb to replace crypto with Bitcoin, I will always try!)