In normal operation almost all laws before parliament are drafted by the government of the day. Parliament could in principle do whatever it wants, but ordinarily in the UK the governing party has a majority (often a sizeable one) in parliament like this present Tory government, which it can whip to support its measures, so it would be futile to resist. The remarkable thing about Brexit was that a majority of members were sure that any particular plan was so bad as to be worth overturning the government position, and so Parliamentary sovereignty mattered.

By convention governments set aside a small amount of time for measures from individual MPs, most of which will be debated but proceed no further if they're at all controversial. A lot of such business will be scheduled for Friday, this way almost everybody can go home. The Speaker (or whichever deputy has to stay on Friday) will claim to hear dissent after a bill is discussed before it can pass, and because there seems to be dissent the house must be divided in order to count supporters for each side of the matter. In doing so it will be "discovered" that it is inquorate (ie there aren't enough members present) and nothing is done.