Another member seconds the motion.
The rights of the minority vs the rights of the majority are balanced by Robert’s Rules. The seconding of a motion prevents one person from making motions that no one else cares to discuss. There are exceptions to the requirement for a second that we will cover later and if debate is entered into a second is assumed.
Step 2: Another member calls out “Second”. The other member does not need to be recognized first. A chair may ask “Is there any second?” if one is not called out.
It is irrelevant who seconded the motion, so long as that person is a member. Some governing documents require entering into the minutes the name of the person who seconds a motion. The person calling “Second,” may not agree with the motion, but may want to show how much opposition there is by voting it down or have it on record as being considered.