Liquid propellants like kerosene and hydrogen peroxide - that's risky, though doable.
Cryofuels like liquid oxygen and hydrogen - no. Even if you manage to develop an amateur rocket motor that's capable of running on these, the infrastructure for storage and manipulating them is out of range of amateurs. Even professionals like SpaceX avoid LH2 and run on kerosene because liquid hydrogen is so ungrateful substance to handle they are better off going with slightly lower efficiency and not needing to handle it.
You may achieve limited success with "high-temperature" cryogenic liquid propellants - LPG, nitrous oxide; stuff that stays liquid above -100C and is not extremely aggressive. It's still a headache not really worth the extra effort. Just getting a stable combustion and not destroying the test setup in the process is a great success. With air moisture forming frost everywhere, boil-off products creating risk of explosion, and need to handle everything in thick gloves or through prongs to avoid frostbite, racing against the clock when boil-off begins, fumes being not really health-neutral etc, you'll have your hands so full there won't be enough left to actually get any work on the engine done.