Yes, but ideally you should have equipment that are compatible with Lithium/LiFePO4 cells.  It will work, and having a good quality BMS
will protect the cells, however having equipment suited to LiFePO4 cells means you will extend the lifespan of your cells.

The answer to this has several variables such as, how much energy are you consuming, the amount of charge your putting back into the battery bank and what is the peak current being drawn at anyone time.  The answer to all these questions will
determine how many cells you need.  Best thing to do is (if possible) measure the amount of energy (Watts) you’re consuming
over the typical day with a Watt Meter. This will give you an idea of how much energy you’re consuming and somewhat determine how many/type of cells you’ll need plus an idea of what solar/turbine/grid power source you’ll need to recharge your battery bank.

The short answer is “YES”, but its not advisable. A BMS is used to ensure that cells within a battery bank is kept balanced or in other words the voltage of each cell is kept somewhat level. A good BMS will also protect the longevity of the LiFePO4 cells against overcharging or over-discharging plus too much current being drawn.

A LiFePO4 sealed battery is simply a battery box with individual LiFePO4 cells and a BMS inside to achieve the voltage of the total pack. For example, a 12V LiFePO4 sealed battery will still have 4 x 3.2volt cells connected in series to achieve 12V (Or actually 12.8V). The key benefit of sealed LiFePO4 cells are they are plug and play, no need to connect cells or the BMS unlike if you buy individual cells. The negative is you don’t actually know what’s inside the sealed battery pack, if the cells are A Grade or used (B Grade) or the type/quality of the BMS. The major negative is that if one of the cells connected in series is to fail, the whole pack will stop working and you’ll need to replace the whole unit, whereas you can simply replace a single cell if you’re you’ve got a battery pack built from individual cells.