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There are standards but a lot depends upon which country/market you are aiming for.
The US has IPC standards, UK has BS standards and guess what, the rest of Europe has European standards....
Most people will use the IPC standards, although there appears to be very little standardisation of schematic drawings. More its a case of "good practise" like not having more than 3 lines into a junction, making line widths thick enough & text big enough for the drawing to be printed/copied well etc.
As for PCB layout, a lot of that is also a matter of experience, what the manufacturing capability is, what the type/class of PCB is etc.
IPC-A-610C, IPC-2152, IPC/EIA J-STD-001C, IPC-SM-782 (now obsolete but still good)IPC-7351 (replaces 782) to name but a few.
Get the pcblibraries/pcbmatrix footprint tools for IPC-7351 (free) to advise you on pad sizes etc, getting good footprints/pad sizes is key to good design.