Please note that in order to obtain employment in Greece, you need to have a work permit, to get a tax ΙD number (AΦΜ) and insurance number (AΜΚΑ) as well AMA number (you get this number from EOPPY the first time you are employed in Greece).
DYPA, the or ΔΥΠΑ (formely known as OAED) is the Greek Public Employment Agency is the main agency in Greece that offers government sponsored employment services. The main services the agency offers includes assistance with the preparation of a CV, guidance in job searching etc.
DYPA has 51 schools around the country on trades and technical training (eg. graphic design, wood-work & furniture making, textile-clothing) . Applicants need to have obtained legal status in Greece, AMKA and a tax ID number in Greece in order to sign up for these schools.
Online toos/search engines:
https://www.mikres-aggelies-ergasias.gr/index.php This site contains a variety of job openings, such as nannies, cleaning personnel, kitchen staff but also other positions in industries such as retail.
A lot of work-related support to refugees, migrants and other TCNs is offered by numerous NGOs in various cities around Greece.
There are centers ΚΕΜ (Migrant Integration Centers) that can provide referrals for professional services and training opportunities.
NGOs such as Metadrasi (https://metadrasi.org/en/home/), Solidarity Now (https://www.solidaritynow.org/en/), and Generation 2.0 (https://g2red.org/) provide employment related services and information.
Metadrasi offers job counselling services such as the Steppingstone project that offers job interview preparation, CV preparation etc.
LinkedIn is also a good platform to create a professional profile and connect with potential employers. Recruiters in Greece use it to find personnel, depending on the company they represent. If you speak a language or languages that are in demand this might be a good place to advertise your skills.
For freelance work:
Upwork-a freelancing platform where you can create a profile for free and find projects as a virtual assistant, translator and a lot of other small or big jobs. To receive payment as a freelancer you to have a VAT in Greece which means that you have to apply to be a free lancer through the Tax Authorities in Greece.