It is not possible to add thickness to your penis except through Surgery which would be painful and expensive. I imagine there is no real need it may just be ego on your part.
Advice has no singular form; the closest is a 'piece of advice'. Proper usages include: give advice give some advice give a piece of advice
to give advice is to give a suggestion
He asked his sister to give him advice about dating.
to give suggestion is advice ideas about what to do is advise
What advice did Polly give to Jerry
Why is it important to give treatment advice and what may happen if advice was not given
Anyone can give advice - however, it's not wise to accept advice from anyone but an expert.
I can give you an answer, some advice, some wisdom, or a quandary.
To get advice
Advice is ideas about what to do while Advise is to give suggestions
The plural form for 'piece of advice' is pieces of advice.
Most lawyers will give you a free consultation, but that's it. They can give you advice, but they won't do anything for you unless you pay them or give them a retainer.