interp is the setting for how much ms it takes for your information to be held before it is sent to the server so you wont lose packets while sending them. lerp is the end result of how much time it takes for your inputs to be sent to the server
just know that these are different ok?
interp definitely is almost just the same as lerp but even if you set your interp to 0 you will still get 15.2 or 30.3 lerp at the end (according to your cl_interp_ratio setting which i will talk about later on this guide)

(RECOMMENDED) FAST FIX: just download and use mastercomfig, mastercomfig will automatically set the lerp settings for the best. it also helps with fps! the link to what im talking about is https://comfig.app
the website is very easily usable and is very helpful
MANUAL FIX: you can make an autoexec.cfg file and put your networking cvars in there, heres a tutorial on how to make an autoexec.cfg and what it even does: https://www.youtube.com/watch?v=1aT7kFj7ZGI
here are the settings i would recommend for anyone doing a manual fix:
for projectile (classes that would use bombs or rockets or arrows and everything inbetween as means of doing damage) classes:
cl_predict 1
cl_interp 0
cl_interp_ratio 0
rate 786432
cl_smooth 0
cl_smoothtime 0
cl_pred_optimize 2
cl_predictweapons 0
for hitscan (for classes that use bullets) classes:
cl_predict 1
cl_interp 0
cl_interp_ratio 2
rate 786432
cl_smooth 0
cl_smoothtime 0
cl_pred_optimize 2
cl_predictweapons 0
now this is of course my recommendations and i might be mistaken in some of these so do your own research aswell!
(if you are experiencing jittering or packet drops, you could try using a higher interp ratio setting and enabling cl_smooth with cl_smoothtime set to 0.1.)

cl_predict
this setting enables or disables predicting enemy positions (always enable this imo) 1=enabled 0=disabled
cl_interp
this setting basically just sets the amount of time it takes for your inputs to be sent in seconds example: cl_interp 0.1 = 100 miliseconds of delay (VERY bad!) cl_interp 0.0303 = 30.3 miliseconds of delay. (much better for every type of class!)
cl_interp_ratio
this setting specifies how many previous ticks the game uses to guess where the enemy will be. example: cl_interp_ratio 3 = 3 previous ticks used for guessing (not good)
setting this to 2 will make your lowest possible lerp 30.3 and 1 will make your lowest possible lerp to 15.2. i dont know about 3 but you could find it out yourself
rate
this setting caps the bandwight the client side is capable of. example: rate 786432 = 6 mb's of game bandwight as a max (this is the max you cant go above this amount)
cl_smooth and cl_smoothtime
basically when theres a misprediction or any error of that sort, the game smoothes out the enemies movement so it doesnt jitter around and looks bad. 0=disabled 1=enabled
smooth time specifies how much time the smoothing happens over.
cl_pred_optimize
this setting optimises the guessing of enemy positions i think this should always be set to 2 because it makes it so that it is much more precise and faster (and also better in terms of emeny position accureteness!)
cl_predictweapons
if enabled your computer guesses the effects of weapons, i dont really know but this should even effect your input latency so this can be set to 1 or 0 if you want to.

PLEASE DONT CHANGE YOUR CL_CMDRATE, CL_UPDATERATE OR TICKRATE EXPECTING TO GET HIGHER TICK RATES! THIS CHANGES NOTHING! THE TICKRATE THE GAME RUNS AT IS SET BY THE SERVER AND NO ONE ELSE (tough you can go lower, but not higher) PLEASE JUST DONT EVEN BOTHER CHANGING THESE SETTINGS IF YOURE GONNA PLAY ON AVERAGE SERVERS.