I am right now in Manali for last 2 months. Rohtang, Sissu, Atal Tunnel are subject to weather conditions....mostly access to these is closed due to snowfall conditions in January.
However you can for sure visit the below:- Old Manali cafes - Rockys, Lazy Dog, Cafe1947
Naggar Castle in Naggar
Apple Orchards in Aleo
Beas Riverside Solang Valley subject to weather/road conditions