how does abel magwitch resemble joe?

Both Joe and Magwitch are the surrogate parents of Pip. In Ch.7 we read of how Joe came to adopt Pip:

I said to her, 'And bring the poor little child. God bless the poor little child,' I said to your sister, 'there's room for him at the forge!'"

Similarly, in Ch.40 Magwitch remarks,

"And this," said he, dandling my hands up and down in his, as he puffed at his pipe; "and this is the gentleman what I made! The real genuine One! It does me good fur to look at you, Pip. All I stip'late, is, to stand by and look at you, dear boy!"

2. However, Pip is always embarrassed by both Joe and Magwitch and would prefer not to have any contact with both of them in London city. In Ch.27 when Joe writes to him saying that he is coming to London to visit him, Pip says:

Let me confess exactly, with what feelings I looked forward to Joe's coming.

Not with pleasure, though I was bound to him by so many ties; no; with considerable disturbance, some mortification, and a keen sense of incongruity. If I could have kept him away by paying money, I certainly would have paid money.

Similarly, throughout Ch. 40 Pip wishes that Magwitch had never come to meet him in London and he does his best to keep Magwitch's presence in his room a secret:

He was to remain shut up in the chambers while I was gone, and was on no account to open the door.

3. Both Magwitch and Joe do not how to eat elegantly using a fork. In Ch.27 Pip is embarrassed by Joe's table manners:

Then he fell into such unaccountable fits of meditation, with his fork midway between his plate and his mouth; had his eyes attracted in such strange directions; was afflicted with such remarkable coughs; sat so far from the table, and dropped so much more than he ate, and pretended that he hadn't dropped it; that I was heartily glad when Herbert left us for the city.

Similarly, in Ch.40 Pip is repulsed by the Magwitch devours his food:

He ate in a ravenous way that was very disagreeable, and all his actions were uncouth, noisy, and greedy.

4. The clothes that both of them wear when they are in London do not suit them. In Ch. 27 Pip describes Joe as,

As to his shirt-collar, and his coat-collar, they were perplexing to reflect upon - insoluble mysteries both. Why should a man scrape himself to that extent, before he could consider himself full dressed?

Similarly, in Ch.40 Pip remarks on Magwitch's dress in the following manner,

Next day the clothes I had ordered, all came home, and he put them on. Whatever he put on, became him less (it dismally seemed to me) than what he had worn before. To my thinking, there was something in him that made it hopeless to attempt to disguise him. The more I dressed him and the better I dressed him, the more he looked like the slouching fugitive on the marshes.

Both Magwitch and Joe were from a low social class, and despised by Pip for their actions