[verb ます-stem] + ながら + [verb]
ながら joins two actions that one person does at the same time: "while ~ing". It goes on the ます-stem of the first verb, the background action, and the verb at the end of the sentence is the main one.
The verb before ながら never changes. Tense and politeness are carried by the last verb.
The main action goes at the end. Swap the two and the sentence says something else.
Both actions belong to the same person. When two people do the two things, use ま間 with ~ている.
These go beyond two actions at the same moment.
ながら also covers two things done over the same months or years.
After a noun, an adjective, or a state such as しっている知っている, ながら means "although". That is the meaning of ながらも, and the set phrase ざんねん残念ながら "unfortunately" comes from it.