The number of reviews each day can be somewhat predictable if you keep a steady pace each day, making sure not to miss a day (spending roughly the same amount of time each day studying). This is important for your memory itself, which is why the SRS is generating reviews when it does. The ideal time to review a word would be when it’s exactly 100% due-- each word you study will become due again. In a nutshell if you studied a word one week ago, and it’s 100% due, that word would become due again in 2 weeks if you mark it as correct, and reset the scheduling if you mark it as incorrect.
You might want to check out the goal mode feature, where you can set a time or review based goal to make sure to hit it every day (and possibly stop for the day when you hit it).
The system is trying to make sure you still remember everything will before it introduces too many new items, however if you’re noticing you seem to remember everything well and the reviews are being shown too early, you could adjust your account’s retention rate (setting it lower), which will generate less reviews. If you find that you don’t remember a portion of the daily reviews, as tedious as reviews may sometimes be, I recommend powering through them without adjusting your retention rate, and to not add any new items until the review number is lower.
Even if you aren’t able to add some new items for awhile while you’re working on getting the daily review number to a manageable level, that will ensure a more consistent amount of reviews without a sudden influx, while solidifying the other items.