You are about where I am, so when someone with more experience chimes in, take their advice, not mine.

Learn any simple OLL/PLL system first, like badmephisto. That way as you learn new algs you can still complete the solve using your old method.

4 look last layer is 1 EOLL, 2 COLL, 3 CPLL, 4 EPLL.

You likely already know EOLL (yellow cross). So you are 25% of the way there, and you haven't even started.

For COLL you have to learn the 7 Corner Orientation algs, and you will have 2-Look OLL done. You probably already know at least one of these, since whatever method you are using to solve the cube now results in all the yellow stickers facing the same direction.

For CPLL, if you know any alg to permute the last layer corners, you can learn more of those, and just use the one you know already if you don't happen to get one of the new cases you have learned. Eventually you will know clockwise 3 cycle, counterclockwise 3 cycle, and E-Perm.

Now all you have to do is EPLL. Again, you likely already know some type of 3 cycle alg. So 3 more algs will give you 3-cycles each direction, H perm, and Z perm.

Also watch