Yes you can go there. Some activities are open But do take precautions. Wait for a few more months. Despite of the government is lifting lockdown, cases are going higher day by day.
Being a revered pilgrimage destination, Rishikesh is quite safe to travel. The road conditions in Rishikesh largely remain unaffected during the monsoons. Local people of Rishikesh are very humble and even make sure that all the tourists are safe and sound.