I am looking to buy btc online using SQUAREUP.com, GOFUNDME.com in form of donations or invoice
I can also do VENMO
anyone
I will only do through escrow
AFAIK all of these payment methods are very easily reversible and the receiver is going to incur a lot of fees to receive the funds.
The most likely scenario in which someone is defrauded by accepting these payment methods would involve some kind of claim that the payment was made with a stolen credit card and/or the transaction was unauthorized. The question of if the transaction is actually unauthorized or not is really not going to matter in the eyes of a bitcoin seller because they would most likely end up loosing the dispute along with any money they were expecting to receive.
If you are using legit funds then I would suggest that you withdraw to cash/your bank account and then offer to buy bitcoin with cash based payment methods