I've recently bought a Btwin Riverside 50 for daily commute. I weigh 94kg and usually ride with a backpack which weights around 3-5kg, I'm worried if the bike can hold my weight or the pedal might break off while standing. If the bike can't hold my weight, I want to know what modifications I can make so that it can hold my weight.
The manual offered with the BTWIN Riverside 50 (click on the bike manual tab) indicates that 100kg is the max weight for your bike. 94 + 5 = 99 so you are under the limit. Max weight limits take into account rough usage. Pedaling while standing and daily commuting is well below rough usage. The pedals on this bike have a large steel rod as the main support with a sheer strength much larger than 200 kg.
No modifications are needed.